Sound Practices Mailing List Files - Volume 1
=========================================================================
From: "alfred trower" <sedht@hotmail.com>
Subject: Re: C37- caution: flames
Date: Tue, 27 Jan 1998 13:38:58 PST
Source: Sound Digest Archive v01.n173
el34@juno.com wrote:
>I know you don't believe in anything you can't measure and quantify,
but
>there are some things in this universe that CANNOT be measured or
>explained, but that doesn't make them any less real or significant. I
>think YOU are the one who needs to get a grip on reality!
>
Everything can be measured or explained, we just haven't figured out how
yet :-).
But hold on there. I think that there's a middle ground that needs to
be found between the strict engineering and the ears only crowd. Most
tweeks are relatively harmless to try in that they can be "undone".
This C37 stuff can't, and as such, should require some degree of hard
evidence that it works, and evidence of exacly how it works. I'm not
going to take your word, or anyone else's for that matter, using
evidence based on listening tests only. You are taking a risk by
applying this stuff to anything simply because it can't be undone.. The
bottom line on this is that it alters the mechanical and resonant
properties of the thing to which it's applied, and as such it is
impossible for it to be universally beneficial.
Now, if there was a guarantee on it to replace the now ruined piece of
equipment should the user of the product deem that it didn't make an
improvement...
To Tom, keep on asking those questions. As far as I'm concerned, I'll
still chose what works and what doesn't by ear. Having said that, I'd
love to know not just that "it does" but "HOW IT DOES IT"! There's far
too much voodoo, smoke and mirrors in the audiophile world, and far too
much play on the insecurites of audiophiles. And as experimenters, I
think we owe it to ourselves, when we find something that works to then
attempt to find out why before we make blanket recommendations.
Al
Alfred Trower
Consultant, Client/Server Systems
Supply Chain Specialist
- ----------------------------------
"The higher we soar the smaller we appear to
those who cannot fly." Friedrich Wilhelm Nietzsche
______________________________________________________
Get Your Private, Free Email at http://www.hotmail.com
=========================================================================
From: el34@juno.com
Subject: Re: C37- caution: flames
Date: Tue, 27 Jan 1998 15:47:57 -0500
Source: Sound Digest Archive v01.n173
On Mon, 26 Jan 1998 15:33:17 -0600 Thomas Danley <tom@ppci.com> writes:
>You won't find a reputable driver company that doesn't refine there
>products using test equipment and use scientific methods to design them,
>the days of designing strictly by ear are long over.
Thats why 90% of it sounds like crap too!
I do use test equipment from time to time, I have a spectrum analyzer,
digital phase and gain meter and some other goodies. I use them when
comparing things in a general sort of way, but the final tweak is always
done by ear. I don't care how something "measures", I only care how it
sounds with the music I listen to.
I know you don't believe in anything you can't measure and quantify, but
there are some things in this universe that CANNOT be measured or
explained, but that doesn't make them any less real or significant. I
think YOU are the one who needs to get a grip on reality!
We know that you take a strictly "engineering" approach to "design", you
have made that abundantly clear. I for one am growing weary of you
pontificating on EVERY aspect of EVERY issue that comes up. You always
have "the" answer for everything., and if someone offers an opinion that
doesn't fit your world view, you try to beat them into submission with a
load of your dogma.
You are taking the fun out of this list, back off and let some other
ideas flow for awhile. You might actually learn something.
I'm sure you will respond to this with your usual style, so I will state
now that I will not carry on a flame war with you. I have stated my
opinion and I will say no more on this subject.
What do you think guys, am I off base here? Maybe I should just sign off
the list until this guy joins the ranks of Andre Jute....
Joe
_____________________________________________________________________
You don't need to buy Internet access to use free Internet e-mail.
Get completely free e-mail from Juno at http://www.juno.com
Or call Juno at (800) 654-JUNO [654-5866]
=========================================================================
From: Michel Paquette <paqm01@GEL.USherb.CA>
Subject: Re: C37- caution: flames
Date: Tue, 27 Jan 1998 16:53:15 -0400
Source: Sound Digest Archive v01.n173
Joe at el34@juno.com goes ballistic...
Ouch! Cool down dude.
Tom said that applying the lacquer will change the response of the
compression driver. Your listening tests agree with this. He is just
saying that it would be nice if you could back up your tests with
measurements. If you you don't have the equipment, energy, time to do
this is fully understandable. The reason for tests using test instruments
is to quantify the effect. Once you understand the exact mechanism of the
effect of the lacquer, then you can improve on it. This method is more
efficient than "trying out every possible combination". That's how science
and engineering works. The computer your are using right now is made of
microchips that were only ideas just a few years ago. The improvements in
fast growing technologies comes from understanding in minute details the
mechanisms. That takes a lot of experimental research and theoretical
modelling.
I just reread your last post. You say you have a spectrum analyser. Can
you measure the changes from applying the lacker?
BTW, I happen to really enjoy Tom's very informative posts.
Michel
=========================================================================
From: Thomas Danley <tom@ppci.com>
Subject: Re: C37- caution: flames
Date: Tue, 27 Jan 1998 18:44:37 -0600
Source: Sound Digest Archive v01.n173
el34@juno.com wrote:
>
> On Mon, 26 Jan 1998 15:33:17 -0600 Thomas Danley <tom@ppci.com> writes:
>
> >You won't find a reputable driver company that doesn't refine there
> >products using test equipment and use scientific methods to design them,
>
> >the days of designing strictly by ear are long over.
>
> Thats why 90% of it sounds like crap too!
I don't think the use of test equipment is what makes drivers sound like
crap, like bad karma or something, rather those in management dictating
ever lower manufacturing costs per driver.
Most of the big speaker companies are marketing driven, FOR PROFIT (in
big letters) and while they project the image they think people want to
see, they spend little effort actually focusing on perfection, look at
#1, a clue, rymes with nose.
> I do use test equipment from time to time, I have a spectrum analyzer,
> digital phase and gain meter and some other goodies. I use them when
> comparing things in a general sort of way, but the final tweak is always
> done by ear. I don't care how something "measures", I only care how it
> sounds with the music I listen to.
>
> I know you don't believe in anything you can't measure and quantify, but
> there are some things in this universe that CANNOT be measured or
> explained, but that doesn't make them any less real or significant. I
> think YOU are the one who needs to get a grip on reality!
We simply dwell at different points in the reality curve, I love music
too but I build loudspeaker drivers for a living, the last few years
that has involved building all of the parts, radiators, magnet
assemblies, coils, frames etc, there is no path for me to to follow,
there are no parts off the shelf. I have to rely on things like the TEF
machine to tell me when I have made a change that brings me closer to
the ideal, changes that I can hear but what am I hearing.
Measurments in the time domain seem particularly important here.
While I agree that there are things in life you can't measure, the flaws
in loudspeakers are generally so large compaired to electronics that
between the various forms of measurments you are likely to find one
where a change is likely to look more dramatic that it sounds, although
there have been a few times when a change that was audible was
reasonably subtile in the measurment.
>
> We know that you take a strictly "engineering" approach to "design", you
> have made that abundantly clear.
In reality I am an inventor, I depend heavily on Intuition especially
when doing something new of to solve a "headscratcher" problem.
I for one am growing weary of you
> pontificating on EVERY aspect of EVERY issue that comes up. You always
> have "the" answer for everything., and if someone offers an opinion that
> doesn't fit your world view, you try to beat them into submission with a
> load of your dogma.
I suppose to some degree I am on a mission, but when I have posted I
have tried to be "light" about things or respond in kind.
In the last 20 years or so I have seen the general public become less
and less interested in the actual quality of sound, this I think is due
to two things primarily. The first is the relentless dilution of the
meaning of language by the marketing departments of companies that
steadily proclaim near perfection while selling ever cheaper to build
products. These days looks are vastly more important than performance
resulting in expensive looking gold plated junk that people buy "cause
its tha best"
As near as I can tell, none of the big companies give a rats ass about
actually providing a genuinly superior product (perhaps that is over
stating it some). These are the companies who's advertising "educates"
the public as to what is "good" or possible.
The other big problem I see is that high end HIFI has to some degree
gotten the image of being a bunch of flakes, ready to buy the next new
snake oil product and the more expensive it is, the better it has to be.
There is no shortage of this kind of product and companies outside the
HIFI area do the same thing, apealing to the bit of "X file" hiding in
all of us. The general rejection of science that hallmarks the newage
movement in general and to some degree HIFI in the long run does all a
diservice.
When I have posted in a confrontitory tone it has only been to challenge
or question things that "smell funny" or are contrary, When I questioned
amplifier topology and measurments, many responded emotionally but
several, in particular Lynn O. had very thoughtfull and helpfull
responses.
>
> You are taking the fun out of this list, back off and let some other
> ideas flow for awhile. You might actually learn something.
Sure, most of the time I do just lurk, however, you might consider your
own advice also.
Like they say " keep an open mind, but not so much that your brain falls
out".
>
> I'm sure you will respond to this with your usual style, so I will state
> now that I will not carry on a flame war with you. I have stated my
> opinion and I will say no more on this subject.
I have no wish for a "flame war" either.
>
> What do you think guys, am I off base here? Maybe I should just sign off
> the list until this guy joins the ranks of Andre Jute....
>
> Joe
"This guy" may go away or may not but it is the lists loss if anyone
who activly contributes goes away, a diversity of opinion make lists a
good place to be and ask questions.
Tom
=========================================================================
From: Robert Jorgensen <robert.jorgensen@advalvas.be>
Subject: Re: C37- caution: flames
Date: Tue, 27 Jan 1998 22:34:17 +0100
Source: Sound Digest Archive v01.n173
At 15:47 27/01/98 -0500, you wrote:
>
>On Mon, 26 Jan 1998 15:33:17 -0600 Thomas Danley <tom@ppci.com> writes:
>
>>You won't find a reputable driver company that doesn't refine there
>>products using test equipment and use scientific methods to design them,
>
>>the days of designing strictly by ear are long over.
>
>Thats why 90% of it sounds like crap too!
>
>I do use test equipment from time to time, I have a spectrum analyzer,
>digital phase and gain meter and some other goodies. I use them when
>comparing things in a general sort of way, but the final tweak is always
>done by ear. I don't care how something "measures", I only care how it
>sounds with the music I listen to.
>
>I know you don't believe in anything you can't measure and quantify, but
>there are some things in this universe that CANNOT be measured or
>explained, but that doesn't make them any less real or significant. I
>think YOU are the one who needs to get a grip on reality!
>
>We know that you take a strictly "engineering" approach to "design", you
>have made that abundantly clear. I for one am growing weary of you
>pontificating on EVERY aspect of EVERY issue that comes up. You always
>have "the" answer for everything., and if someone offers an opinion that
>doesn't fit your world view, you try to beat them into submission with a
>load of your dogma.
>
>You are taking the fun out of this list, back off and let some other
>ideas flow for awhile. You might actually learn something.
>
>I'm sure you will respond to this with your usual style, so I will state
>now that I will not carry on a flame war with you. I have stated my
>opinion and I will say no more on this subject.
>
>What do you think guys, am I off base here? Maybe I should just sign off
>the list until this guy joins the ranks of Andre Jute....
>
>Joe
>
>_____________________________________________________________________
>You don't need to buy Internet access to use free Internet e-mail.
>Get completely free e-mail from Juno at http://www.juno.com
>Or call Juno at (800) 654-JUNO [654-5866]
>
>
Why does it have to be so aggressive? I just cannot for the life of me
understand it. I'm not gunning for Joe in particular here, since we have
had our fair share of aggression on this list not to talk about other venues.
You get at Tom for designing things. I am not a designer(at least not of
audio components), but I can't imagine how you can design anything without
having the faintest idea how or why it works. That certainly goes for the
things I do design i.e. software systems(which might or might not work very
well of course).
I'm sure that everybody here including Tom takes listening to products very
serious (otherwise I don't think they would be here for more than a few days).
Of course designers do stumble uppon fortunate ideas, but in general there
is more work than accident involved in getting something new and
revolutionary to work properly. And if you stumble uppon something
fantastic, it is also my impression that you will have a pretty good go at
finding out what is going on so that you can reliably repeat it and perhaps
apply the knowledge somewhere else. This goes for Tom, who has proven to a
very laterally thinking mind, but I'm sure it goes equally for Mike or Doc B.
Personally I'm intrigued by C37. While the explanation seems a bit far out
I certainly appreciate the connection with the craftsmanship of yore and
the lost secrets of how to build Stradivari and the likes. I would like to
have a chance to try it, but if it actually works (most people who have
tried it, that I know says it does), I would equally like to have some more
insight into why it does so. If nothing else so that one could perhaps
prove that the secret of the old instrument builders were in the laquer.
It would be interresting to have some info from Karl-Heinz (I forget his
last name) from ALR-JORDAN who as far as I know have decided to use C37 on
their best model.
We need listening, an open mind as well as understanding to make real
progress.
Greetings and peace from Brussels
Robert Jorgensen
Robert.Jorgensen@advalvas.be
=========================================================================
From: Marc Elmlund <marc@wineasy.se>
Subject: Re: C37- caution: flames
Date: Tue, 27 Jan 1998 22:46:19 +0100
Source: Sound Digest Archive v01.n173
At 15.47 -0500 98-01-27, el34@juno.com wrote:
>I know you don't believe in anything you can't measure and quantify, but
>there are some things in this universe that CANNOT be measured or
>explained, but that doesn't make them any less real or significant. I
>think YOU are the one who needs to get a grip on reality!
You tell him, Agent Mulder ;-)
Marc Elmlund
Stockholm, Sweden
aka marc@wineasy.se
=========================================================================
From: Finn Hammer <f-hammer@post5.tele.dk>
Subject: Re: C37- caution: flames
Date: Tue, 27 Jan 1998 23:14:27 +0100
Source: Sound Digest Archive v01.n173
el34@juno.com wrote:
> What do you think guys, am I off base here?
Frankly, now that you ask....yes, I think you are.
I think Tom has come with a lot of usefull stuff, not many guys here that actually
design speakers themselves.
So the guy is a scientist, so what!, doesn`t mean you have to respond to everything he
says, as if it was the gospel truth.
But surely, none of the really good stuff whould have been made without synergy btwn.
science and craft. To mention Thuras and Wenthe, It is always good to have a "Wenthe"
around.
Maybe I should just sign off
> the list
Nah.. you have already spotted your problem, just use the delete key with determination.
You know, self moderation.......(of the list)
>until this guy joins the ranks of Andre Jute....<
- -Who was flamed outa`here,( and blody well asked for it, too ) and you will say nothing
more yourself. That leaves the rest of us to do it for you!
If that is the mood you are in, perhaps it would be a good idea to sign off for a while,
and cool off a bit.
finn, deleting 3/4
=========================================================================
From: William Hunt <wjhunt@ccnet.com>
Subject: Re: C37- caution: flames
Date: Tue, 27 Jan 1998 17:45:31 -0800
Source: Sound Digest Archive v01.n174
Thomas Danley wrote:
> > >You won't find a reputable driver company that doesn't refine there
> > >products using test equipment and use scientific methods to design them,
> >
> > >the days of designing strictly by ear are long over.
> >
> > Thats why 90% of it sounds like crap too!
>
> I don't think the use of test equipment is what makes drivers sound like
> crap, like bad karma or something, rather those in management dictating
> ever lower manufacturing costs per driver.
...
I've been a lurker for some time on this list. I want to support Mr.
Danley on this issue of measurement versus individual subjective
criteria.
There is nothing wrong with using your ears. However, if you want to
build a number of units and have them all sound the same, you had better
understand what characteristics of the prototype must be present in the
production units. For example, you may feel that high end resistors
sound much better than cheap ones. But you had better get the
resistance right; the world's best resistor in the wrong value is no
improvement to a circuit.
Suppose that you believe strongly that material from (once) living
plants makes for much better sound than inorganic materials. You might
want to use carrots as capacitors, radishes as resistors and turnips as
amplifying elements. The tuber philosophy you might call it. Your
faith might be strong but I think your chances of success would be poor.
Electronics is based on knowledge and measurement. Real progress
requires extending the base of knowledge. Intuition and subjective
judgement can often lead to a breakthru but to give a lasting effect, it
has to lead to more knowledge and better measurement. It has to be
transferrable to other people and repeatable captured in real-world
measurements.
Bill Hunt
=========================================================================
From: Joe Pledger <doodle@navicom.com>
Subject: Re: C37- caution: flames
Date: Tue, 27 Jan 1998 19:24:30 -0800
Source: Sound Digest Archive v01.n174
Thomas Danley wrote:
- -big snip-
Well, of course! Welcome to reality! Most things are driven by the
"bean-counters", who are naturally the new grads (with tuition bills)
and six months to get in and make their mark. ( And you thought
prostitution was the oldest profession!!;-)) Those who make it
eventually become CEOs and become rich if they lay enough people off.
Anyone else has made a prior decision to go for art, or some other
field with delayed gratification factor. I guess my point is: Please
value the discussion and concepts found here on the joenet. You won't
find the same in any sales brochure (that I've ever seen). Tom, I agree
with you. If it's a Corporate activity, it's driven by the stock market
and there is no reality involved. Any sense of producing a valued
product has no place in the market formula. Imagined worth is
everything!
Side subject: Someone mentioned Ferrari. (from a comment of another
joenetter).
My youngest went through two of them a few years ago. I told him I
thought it was an plot to promote the imigration of mechanics to the
USfrom Italy. Granted, he had the 308 series (which even farrari says
is their "Rough" model). But he was averaging $200 per month over the
ownership period just for clutch adj/repair work. Still when I ask him
what car of all did you love the best? He'll say the Ferrari!
I just don't understand the kid...I thought his Lotus was the best!
So what am I getting at? Well everyone's ears, scientific approach,
measurements, hookup scheme, room acoustics, mood, and probable hormonal
levels, quality of wine, you name it, is up for argumentative analysis
if one is so inclined. Flame activity tends to inhibit the free exchange
of detail and content. There is a really great spirit of free exchange
here, lets keep it going! OK, so I have tin ears!
Sorry Tom, this wasn't really especially aimed at you, just tagged on
I guess.
Joe Pledger
> Tom
=========================================================================
From: Joe Pledger <doodle@navicom.com>
Subject: Re: C37- caution: flames
Date: Tue, 27 Jan 1998 19:41:58 -0800
Source: Sound Digest Archive v01.n174
William Hunt wrote:
>
> Thomas Danley wrote:
>
> want to use carrots as capacitors, radishes as resistors and turnips as
> amplifying elements. The tuber philosophy you might call it. Your
> faith might be strong but I think your chances of success would be poor.
>
-snip-
Agreeded, I'm getting around 200K on a 2 inch peeled carrot, with probes
inserted 1/8th inch in the ends. Can't get a steady measurement. May be
a good substitue for the CCS.
I should really check the capacitance! Should I use a metal or plastic
clip to hold this on the chassis?
Course,it just came out of the fridge, so there's going to be a drying
effect which needs study.
Sorry, and thanks for putting up with me tonight, we're doing a wine
tasting thingey (Hey Edie, did anyone show up yet? Do we have any
turnips?);-)
Joe Pledger
> Bill Hunt
=========================================================================
From: "Mark K. Long" <long@robby.caltech.edu>
Subject: Re: C37- caution: flames
Date: Tue, 27 Jan 1998 20:23:24 -0800
Source: Sound Digest Archive v01.n174
>
>What do you think guys, am I off base here? Maybe I should just sign off
>the list until this guy joins the ranks of Andre Jute....
>
Honestly, you are off base. Don't worry about it, we all have bad days
and need to vent.
I've never heard any of Tom's audio gear, so he could be just as
looney as the rest of us, but the fact that he's really built things
and is making a honest effort to reconcile performance and
measurements makes his contributions very valuable to me. Unlike
Mr. Jute, whose pages and pages of prose would leave me feeling empty,
my delete key pauses when Tom is on the "From:" line, because I know it
could make think about things in a different way.
I find it interesting that in an endeavor whose results we all have
trouble quantifying, that there is so much attachment to pet
theories. Perhaps it is precisely because there are so few absolutes
that we struggle to find something to hold on to as the "truth", and
get so defensive when that truth is questioned in any way.
SE?, PP?, SS?, C37?, CD?, LP? I have no idea, speakers are giving me
enough heartache, I'll go back to lurking, till the next good horn
discussion. Anyone want to talk about dispersion or waveguides?
setting or measuring Q on a horn?
Mark
=========================================================================
From: RALPH POWER <POWER.RALPH@epamail.epa.gov>
Subject: Re: C37- caution: flames -Reply
Date: Tue, 27 Jan 1998 16:39:37 -0500
Source: Sound Digest Archive v01.n173
Hi Joe,
You said:
>but the final tweak is always done by ear. I don't care how something "measures",
>I only care how it sounds with the music I listen to.
>there are some things in this universe that CANNOT be measured or
>explained, but that doesn't make them any less real or significant.
I agree wholeheartedly with the above statements and I bet more than a few others
around here do too.
I have never measured my amp and have nothing to measure mine with, but it is the
best sounding amp I have ever had. And I keep making it a little better as I go along.
I don't need a measurement to verify that for me.
We should feel free here to express our findings and impressions here without worrying
about being ridiculed or flamed.
One should take any information from here in the spirit it is given, your mileage may
indeed vary...
A person who professes to know everything only betrays his true ignorance.
I am firmly convinced of my own ignorance.
My 2 cents,
- - Ralph
=========================================================================
From: "Ken Dangerfield" <bpyakd@mail.island.net>
Subject: C37 lack
Date: Fri, 23 Jan 1998 14:25:24 -0800
Source: Sound Digest Archive v01.n168
Has anyone who has used C37 had a chance to A/B compare it with other
coatings? The point being to identify (if possible) whether there is
something specify to the formulation of C37 which accounts for the
perceived sonic improvements, or whether another suitable coating
(lacquer??) would achieve the same result in some or all situations.
Regards,
Ken Dangerfield
=========================================================================
From: Holger Stein <STEINMUSIC@compuserve.com>
Subject: C37 practice
Date: Fri, 23 Jan 1998 21:26:03 -0500
Source: Sound Digest Archive v01.n169
Hallo,
First of all I must say that I am astonished that more people in America
than I expected were using C37 Lack,as it is based on a very uncommon idea.
Here in Europe we meanwhile got lots of throughout positive feedback from
people who lacquered things I would not have dreamt of, and C37 is going to
become a widely accepted concept now.
To Doc B.: Your idea to airbrush C37 Lack is very good.The surfaces you can
get this way are excellent, and the effect too.
I am not sure in which form you got the Lack, but one set now also contains
a special thinner, so that it is no problem to airbrush it.
To Ken Dangerfield: Other coatings may work well in a specific case,but the
effect of C37 Lack if it is correctly aplicated is always positive, no
matter where you use it. We got a wide range of experiences concerning the
use of E's C37 Lack, and if you have any questions, please let me know.
Best regards
Holger Stein
STEIN HIFI SYSTEMS
Scharpenberg 64a
D- 45468 Muelheim
Germany
Fon ++49 208 32089
Fax ++49 208 390938
GSM ++49 172 4744254
STEINMUSIC@Compuserve.com
Worldwide distribution for Ennemoser's C37 Lack
and much more...
=========================================================================
From: Kalman Rubinson <rubinsnk@is2.nyu.edu>
Subject: Re: C37 practice
Date: Fri, 23 Jan 1998 22:49:27 -0500 (EST)
Source: Sound Digest Archive v01.n169
On Fri, 23 Jan 1998, Holger Stein wrote:
> First of all I must say that I am astonished that more people in America
> than I expected were using C37 Lack,as it is based on a very uncommon idea.
Uncommon? More like strange. The stuff may work but the derivation is
weird.
Kal
=========================================================================
From: "Norman Tracy" <ntracy@galstar.com>
Subject: C37 special coming, was:C37-The Idea and links
Date: Fri, 30 Jan 1998 00:08:03 -0600
Source: Sound Digest Archive v01.n175
Apologies to the list for the private content, but I need to be sure Holger
sees this in case we have a e-mail failure.
To Holger,
You wrote:
"Have to talk about this with Norman (where are you?), who is able to
distribute the stuff."
Did you get my e-mail of 1/28/98 discussing a Joe-net special of C37? If
not I can resend.
To Joe-netters:
As soon as Holger & I overcome the e-mail glitches (if any) and Germany to
USA time difference watch for a special offer on C37.
happy listening
Norman Tracy
Audio Crafters Guild
ntracy@galstar.com
http://galstar.com/~ntracy/ACG/
=========================================================================
From: Daniel Normolle <monk@umich.edu>
Subject: Re: C37 Speziallack & mks equivalents
Date: Tue, 03 Feb 1998 08:58:07 -0500
Source: Sound Digest Archive v01.n180
Norman Tracy wrote:
> Joenetter's,
>
> With all the interest in Ennemoser's C37 Speziallack on the Sound Practices
> mailing list Holger & I thought it would be good to run a special deal so
> you can try it and hear for yourselves.
>
> The regular US price will be $95 per kit. During February the Joenet
> special introductory price is $75 per kit.
> Each 'kit' includes:
> 10 ml of C37
> 10 ml of thinner
> application brush.
>
For those of you still having trouble with metric-to-English conversions,
10 ml equals two teaspoons.
dpn
=========================================================================
From: "Norman Tracy" <ntracy@galstar.com>
Subject: C37 Speziallack - regular pricing & Feb. special
Date: Mon, 2 Feb 1998 23:27:57 -0600
Source: Sound Digest Archive v01.n180
Joenetter's,
With all the interest in Ennemoser's C37 Speziallack on the Sound Practices
mailing list Holger & I thought it would be good to run a special deal so
you can try it and hear for yourselves.
The regular US price will be $95 per kit. During February the Joenet
special introductory price is $75 per kit.
Each 'kit' includes:
10 ml of C37
10 ml of thinner
application brush.
I have both the 20C lack for ambient temperature use and the 35C lack for
use inside equipment.
I have discovered C37 can be removed from circuit boards using flux
remover. Thus if you do not like it or need a spot off for further
soldering it can be removed. I would not try flux remover on your speaker
cones! :-) There I would consider the application non-reversible!!
happy listening
Norman Tracy
Audio Crafters Guild
ntracy@galstar.com
http://galstar.com/~ntracy/ACG/
=========================================================================
From: Thomas Danley <tom@ppci.com>
Subject: Re: C37 Speziallack - regular pricing & Feb. special
Date: Tue, 03 Feb 1998 08:57:31 -0600
Source: Sound Digest Archive v01.n180
Norman Tracy wrote:
>
> Joenetter's,
>
> With all the interest in Ennemoser's C37 Speziallack on the Sound Practices
> mailing list Holger & I thought it would be good to run a special deal so
> you can try it and hear for yourselves.
>
> The regular US price will be $95 per kit. During February the Joenet
> special introductory price is $75 per kit.
> Each 'kit' includes:
> 10 ml of C37
> 10 ml of thinner
If one assumed that the thinner was normal hydrocarbon chemistry (cheap)
the the cost of the C-37 at its reduced price is $28,382.00 per gallon
which seems kind of pricey, but still cheaper than $35,957.00 for the
"normal" price. By weight, at the non sale price,this stuff is about the
same price as pure solid gold. It must be they intend to sell it to
military procurement agencies. In any case the price eliminates the
practical use of it in a production sense.
Tom
=========================================================================
From: "Sellek, Grant (TSA)" <Grant.Sellek@roads.sa.gov.au>
Subject: RE: C37-The FAQ's
Date: Tue, 27 Jan 1998 22:41:55 +1030
Source: Sound Digest Archive v01.n172
Thanks for this explanation. Here are a couple more questions that
SHOULD be FAQ's
1 How many instrument makers (not including Herr Ennemoser) use C37
on their acoustic instruments? What are their instruments? And (just for
fun) what colour are their instruments?
2 What are the main objections to using C37?
3 What can possibly go wrong from using C37? In any application?
4 Is there some really really expensive ingredient in C37 that makes
it so expensive? Or is Herr Ennemoser just overpricing it so that he
recovers all the patent's worth (his time and experience and experiments
over the years etc. etc.) before the first ten litres are sold?
Surely at half the price he could sell more than double the quantity,
and the same for one tenth the price and 10X the quantity. The
ingredients are probably diagnosable by a chemist, so pricing should not
depend on secrecy so much as normal production and distribution costs
plus the inventor's entitlement.
I doubt that I could afford enough C37 to coat the pair of 15-inch paper
cone drivers for my horn speakers. Nobody objects to Herr Ennemoser
earning his entitlements, but I'll wager that most people would be
happier if he had a wider customer base by lower pricing, so each of us
made a smaller personal contribution!
Grant Sellek
Adelaide, Australia
grant.sellek@roads.sa.gov.au
>----------
>From: Holger Stein[SMTP:STEINMUSIC@compuserve.com]
>Sent: Tuesday, 27 January 1998 8:17 pm
>Cc: Dieter Ennemoser; INTERNET:sound@mail.tpoi
>Subject: Re: C37-The Idea and links
>
>Hallo Thomas,
<<cut>>
>here some frequently asked questions answered by Mr. Ennemoser himself:
<<cut>>
> Dieter Ennemoser
>
=========================================================================
From: Kalman Rubinson <rubinsnk@is2.nyu.edu>
Subject: RE: C37-The FAQ's
Date: Tue, 27 Jan 1998 11:05:53 -0500 (EST)
Source: Sound Digest Archive v01.n173
On Tue, 27 Jan 1998, Sellek, Grant (TSA) wrote:
> Thanks for this explanation. Here are a couple more questions that
> SHOULD be FAQ's
>
> 1 How many instrument makers (not including Herr Ennemoser) use C37
> on their acoustic instruments? What are their instruments? And (just for
> fun) what colour are their instruments?
I fail to see the relevance of this.
Kal
=========================================================================
From: Michel Paquette <paqm01@GEL.USherb.CA>
Subject: Re: C37-The FAQ's
Date: Tue, 27 Jan 1998 15:55:21 -0400
Source: Sound Digest Archive v01.n173
Hello Finn and others,
Finn said:
I once asked the owner of a motorsycle shop, why the glass for the
taillight was so
expensive, and he replied: Because i can`t get more.
The pricing of audio gear and accessories follow that rule, I think.
Well, this may be true with anything that hasn't been made in 30 or 50
years, but I often think that audio accessories are a scam. Peter Belt,
Mpingo disks, David Lucas and such. I think the prices are ridiculous
also: like a CD that "supposed to break-in a hifi" selling for over
hundred bucks. C'mon. Just read any advertisement on cables in
Stereophile or Audio for really off the wall claims.
I'm not saying that all accessories are junk but there are many people who
seem to exploit the insecurities of audiophiles.
Sorry for the rant.
Michel
=========================================================================
From: Finn Hammer <f-hammer@post5.tele.dk>
Subject: Re: C37-The FAQ's
Date: Tue, 27 Jan 1998 20:19:34 +0100
Source: Sound Digest Archive v01.n173
This is an interesting discussion.
I`ve used the stuff on my LOWTHER PM2 A`s, and am satisfied with it, As Joe R.
mentioned in his article about the Lowther clubs, any substance known to man has, at
one time been smeared on a lowther cone, and although my father was a painter,(so
I`ve seen many kinds of lacquer) I waited over 20 years, to finally get the lacquer
that i would trust to better my lowthers.
In my view, we should consider it a stroke of luck that we are able to benefit from
the findings of an instrument maker, who takes an interest in reproducing music, gets
original ideas, and then actually lets us have some of his lacquer _at all_.
Think about all the hassle about trying to make a replica of the Stradivarius
Lacquer: said to be the secret of its sound. Couldn`t be done, the guy took the
recipe in the grave.
A loudspeaker cone with C37: I can`t help but comparing it to those beautifull
japanese lacquered boxes. They, too, would be just common junk without the topcoat.
Then there is the issue of the pricing, and frankly, I think it is a disaster. When I
opened the carton, I thought: "Boy, Holger; you shure are pushing this to the edge".
It will assure that the acceptance of the concept of the C37 sound will spread
unnecessaryly slow.
This product deserves to be judged by it`s merits, rather than its price, or else,
this will be for the few, like WE 300 B and other overpriced products.
I once asked the owner of a motorsycle shop, why the glass for the taillight was so
expensive, and he replied: Because i can`t get more.
The pricing of audio gear and accessories follow that rule, I think.
Finn
=========================================================================
From: Kalman Rubinson <rubinsnk@is2.nyu.edu>
Subject: RE: C37-The FAQ's
Date: Tue, 27 Jan 1998 21:10:36 -0500 (EST)
Source: Sound Digest Archive v01.n174
On Wed, 28 Jan 1998, Sellek, Grant (TSA) wrote:
> >From: Kalman Rubinson[SMTP:rubinsnk@is2.nyu.edu]
> >> 1 How many instrument makers (not including Herr Ennemoser) use C37
> >> on their acoustic instruments? What are their instruments? And (just for
> >> fun) what colour are their instruments?
> >I fail to see the relevance of this.
>
> The only relevance, in my mind, is that if other instrument makers are
> buying the C37 in the one litre "manufacturer's quantity" and using it
> on their instruments, it would indicate some breadth of acceptance
> amongst his peers that the product is effective in improving the sound
> quality of acoustic instruments. Since H. Ennemoser's product's
> credibility in hifi circles seems to include reference to the
> instrument-making side, then this side could be discussed more openly in
> a FAQ.
The performance required of an instrument which makes a sound is
different from that required of a speaker which has the task of
reproducing that same sound. Hence, I still see no relevance in this
matter.
Kal
=========================================================================
From: jdougher@tir.com (jdougher)
Subject: RE: C37-The FAQ's
Date: Tue, 27 Jan 1998 22:41:56 -0500 (EST)
Source: Sound Digest Archive v01.n174
On Wed, 28 Jan 1998, Sellek, Grant (TSA) wrote:
> >From: Kalman Rubinson[SMTP:rubinsnk@is2.nyu.edu]
> >> 1 How many instrument makers (not including Herr Ennemoser) use C37
> >> on their acoustic instruments? What are their instruments? And (just for
> >> fun) what colour are their instruments?
> >I fail to see the relevance of this.
>
> The only relevance, in my mind, is that if other instrument makers are
> buying the C37 in the one litre "manufacturer's quantity" and using it
> on their instruments, it would indicate some breadth of acceptance
> amongst his peers that the product is effective in improving the sound
> quality of acoustic instruments. Since H. Ennemoser's product's
> credibility in hifi circles seems to include reference to the
> instrument-making side, then this side could be discussed more openly in
> a FAQ.
The performance required of an instrument which makes a sound is
different from that required of a speaker which has the task of
reproducing that same sound. Hence, I still see no relevance in this
matter.
Kal
I want some of the C 37, it would be great for the barbecue this summer. The
flames
would never go out. The problem with this stuff is that it is to high for us
skeptics to try and not high enough for the gold plate crowd. How about a two
tier price structure one for the Joes and one for the rest of the world. Sounds
like a good idea and why not a discount from the hardware guys too. Well we
could
dream couldn't we.
Jim
=========================================================================
From: Bob Chernofsky <bobc@mci2000.com>
Subject: Re: C37-The FAQ's
Date: Wed, 28 Jan 1998 00:40:02 -0800
Source: Sound Digest Archive v01.n174
- -----Original Message-----
From: Kalman Rubinson <rubinsnk@is2.nyu.edu>
To: Sellek, Grant (TSA) <Grant.Sellek@roads.sa.gov.au>
Cc: 'INTERNET:sound@mail.tpoi' <sound@deliverator.io.com>
Date: Tuesday, January 27, 1998 6:25 PM
Subject: RE: C37-The FAQ's
>On Wed, 28 Jan 1998, Sellek, Grant (TSA) wrote:
>
>> >From: Kalman Rubinson[SMTP:rubinsnk@is2.nyu.edu]
>> >> 1 How many instrument makers (not including Herr Ennemoser) use C37
>> >> on their acoustic instruments? What are their instruments? And (just
for
>> >> fun) what colour are their instruments?
>> >I fail to see the relevance of this.
>>
>> The only relevance, in my mind, is that if other instrument makers are
>> buying the C37 in the one litre "manufacturer's quantity" and using it
>> on their instruments, it would indicate some breadth of acceptance
>> amongst his peers that the product is effective in improving the sound
>> quality of acoustic instruments. Since H. Ennemoser's product's
>> credibility in hifi circles seems to include reference to the
>> instrument-making side, then this side could be discussed more openly in
>> a FAQ.
>
>The performance required of an instrument which makes a sound is
>different from that required of a speaker which has the task of
>reproducing that same sound. Hence, I still see no relevance in this
>matter.
>
>Kal
>
It seems clear to me what the point is Kal. If C37 is said to have a
positive effect on all things when it comes to sound, and resonance one
would hope it would have acceptance in other circles.
Bob
=========================================================================
From: Kalman Rubinson <rubinsnk@is2.nyu.edu>
Subject: Re: C37-The FAQ's
Date: Wed, 28 Jan 1998 10:30:39 -0500 (EST)
Source: Sound Digest Archive v01.n174
On Wed, 28 Jan 1998, Bob Chernofsky wrote:
> It seems clear to me what the point is Kal. If C37 is said to have a
> positive effect on all things when it comes to sound, and resonance one
> would hope it would have acceptance in other circles.
I can't agree. "positive effect on all things" is a bit much to swallow.
Kal
=========================================================================
From: Bob Chernofsky <bobc@mci2000.com>
Subject: Re: C37-The FAQ's
Date: Wed, 28 Jan 1998 11:36:19 -0800
Source: Sound Digest Archive v01.n174
- -----Original Message-----
From: Kalman Rubinson <rubinsnk@is2.nyu.edu>
To: Bob Chernofsky <bobc@mci2000.com>
Cc: Sellek, Grant (TSA) <Grant.Sellek@roads.sa.gov.au>;
'INTERNET:sound@mail.tpoi' <sound@deliverator.io.com>
Date: Wednesday, January 28, 1998 7:30 AM
Subject: Re: C37-The FAQ's
>On Wed, 28 Jan 1998, Bob Chernofsky wrote:
>
>> It seems clear to me what the point is Kal. If C37 is said to have a
>> positive effect on all things when it comes to sound, and resonance one
>> would hope it would have acceptance in other circles.
>
>I can't agree. "positive effect on all things" is a bit much to swallow.
>
>Kal
I am no saying that it does. I am saying the info seems to support this type
of claim. If this is the case it would be informative to see application,
other than audio.
Bob
=========================================================================
From: "Sellek, Grant (TSA)" <Grant.Sellek@roads.sa.gov.au>
Subject: RE: C37-The FAQ's
Date: Wed, 28 Jan 1998 12:19:58 +1030
Source: Sound Digest Archive v01.n174
>From: Kalman Rubinson[SMTP:rubinsnk@is2.nyu.edu]
>On Tue, 27 Jan 1998, Sellek, Grant (TSA) wrote:
>
>> 1 How many instrument makers (not including Herr Ennemoser) use C37
>> on their acoustic instruments? What are their instruments? And (just for
>> fun) what colour are their instruments?
>
>I fail to see the relevance of this.
The only relevance, in my mind, is that if other instrument makers are
buying the C37 in the one litre "manufacturer's quantity" and using it
on their instruments, it would indicate some breadth of acceptance
amongst his peers that the product is effective in improving the sound
quality of acoustic instruments. Since H. Ennemoser's product's
credibility in hifi circles seems to include reference to the
instrument-making side, then this side could be discussed more openly in
a FAQ.
Grant
Grant Sellek
Adelaide, Australia
grant.sellek@roads.sa.gov.au
=========================================================================
From: Dale.Simon@ps.net
Subject: Re[2]: C37-The FAQ's
Date: Wed, 28 Jan 1998 16:51:00 -0600
Source: Sound Digest Archive v01.n174
Kal wrote:
"The performance required of an instrument which makes a sound is
different from that required of a speaker which has the task of
reproducing that same sound. Hence, I still see no relevance in this
matter."
Hi,
After reading the original article, it seems that Ennemoser's
theory was that the mechanics of the human ear produce a
specific distortion spectra that the brain naturally filters
out. He went further, to suggest that if one could alter the
distortions of an instrument or any music or sound producing
mechanism to match the natural distortions of the human ear,
then the brain would more easily filter out those distortions
and the sound would be more natural. So, if his theory is
correct, and C37 lacquer alters the distortion spectra of
everything it touches to be identical or closer to that of the
human ear, then even though the unit does not measure as well,
its faults will be imperceptible to our hearing. Of course,
your pets will probably hate it.
Dale "still waiting for SP" Simon
=========================================================================
From: Kalman Rubinson <rubinsnk@is2.nyu.edu>
Subject: Re: Re[2]: C37-The FAQ's
Date: Wed, 28 Jan 1998 17:34:43 -0500 (EST)
Source: Sound Digest Archive v01.n174
On Wed, 28 Jan 1998 Dale.Simon@ps.net wrote:
> After reading the original article, it seems that Ennemoser's
> theory was that the mechanics of the human ear produce a
> specific distortion spectra that the brain naturally filters
> out.
Nonsense. There's no evidence for this.
Kalman Rubinson
Associate Professor of Physiology and Neuroscience
Director of Medical Neuroscience
=========================================================================
From: Carter Hendricks <carterh@crl.com>
Subject: Re: Re[2]: C37-The FAQ's
Date: Wed, 28 Jan 1998 19:01:41 -0800 (PST)
Source: Sound Digest Archive v01.n174
On Wed, 28 Jan 1998 Dale.Simon@ps.net wrote:
> Kal wrote:
> "The performance required of an instrument which makes a sound is
> different from that required of a speaker which has the task of
> reproducing that same sound. Hence, I still see no relevance in this
> matter."
>
> Hi,
> After reading the original article, it seems that Ennemoser's
> theory was that the mechanics of the human ear produce a
> specific distortion spectra that the brain naturally filters
> out. He went further, to suggest that if one could alter the
> distortions of an instrument or any music or sound producing
> mechanism to match the natural distortions of the human ear,
> then the brain would more easily filter out those distortions
> and the sound would be more natural. So, if his theory is
> correct, and C37 lacquer alters the distortion spectra of
> everything it touches to be identical or closer to that of the
> human ear, then even though the unit does not measure as well,
> its faults will be imperceptible to our hearing. Of course,
> your pets will probably hate it.
>
> Dale "still waiting for SP" Simon
>
The problem with half-crazy ideas is that there's always that
other half.
Amidst all the other stuff in the current issue of Missouri
Conservationist is an article, "Nature's Noisemaker," about
how to make a real good turkey call using the hollowed-out
leg bones of a turkey.
Doesn't prove anything.
But an interesting idea.
And a good way to fool a turkey... the article says Indians
have used such bone horns for 8000 years.
--Carter
=========================================================================
From: Tom Suit <tsuit@UU.NET>
Subject: Re: Re[2]: C37-The FAQ's
Date: Thu, 29 Jan 1998 10:26:17 -0600
Source: Sound Digest Archive v01.n175
At 05:34 PM 1/28/98 -0500, Kalman Rubinson wrote:
>On Wed, 28 Jan 1998 Dale.Simon@ps.net wrote:
>
>> After reading the original article, it seems that Ennemoser's
>> theory was that the mechanics of the human ear produce a
>> specific distortion spectra that the brain naturally filters
>> out.
>
>Nonsense. There's no evidence for this.
>
>Kalman Rubinson
>Associate Professor of Physiology and Neuroscience
>Director of Medical Neuroscience
What evidence is there against it?
-Tom Suit
=========================================================================
From: Kalman Rubinson <rubinsnk@is2.nyu.edu>
Subject: Re: Re[2]: C37-The FAQ's
Date: Thu, 29 Jan 1998 10:49:53 -0500 (EST)
Source: Sound Digest Archive v01.n175
On Thu, 29 Jan 1998, Tom Suit wrote:
> What evidence is there against it?
That's not how science works. If you propose something that no one has
seen, thought of or demonstrated before, it is incumbent on you to present
some evidence.
Kal
=========================================================================
From: Kalman Rubinson <rubinsnk@is2.nyu.edu>
Subject: Re: Re[2]: C37-The FAQ's
Date: Thu, 29 Jan 1998 10:52:57 -0500 (EST)
Source: Sound Digest Archive v01.n175
On Thu, 29 Jan 1998, Tom Suit wrote:
> What evidence is there against it?
My other response was a general one. However, there is quite a bit of
evidence against the proposal. Most neurophysiology books adequately
describe auditory transduction and the data do not indicate a
characteristic noise component in the signals. If you propose otherwise,
present data.
Kal
=========================================================================
From: Tom Suit <tsuit@UU.NET>
Subject: Re: Re[2]: C37-The FAQ's
Date: Thu, 29 Jan 1998 12:02:19 -0600
Source: Sound Digest Archive v01.n175
At 10:49 AM 1/29/98 -0500, Kalman Rubinson wrote:
>On Thu, 29 Jan 1998, Tom Suit wrote:
>
>> What evidence is there against it?
>
>That's not how science works. If you propose something that no one has
>seen, thought of or demonstrated before, it is incumbent on you to present
>some evidence.
Yes, but you said it was "ridiculous". That kind of statement suggests that
there is evidence to the contrary. Personally, I'm suspicious of it as bones
are largely calcium, not carbon.
-Tom
=========================================================================
From: Kalman Rubinson <rubinsnk@is2.nyu.edu>
Subject: Re: Re[2]: C37-The FAQ's
Date: Thu, 29 Jan 1998 12:18:28 -0500 (EST)
Source: Sound Digest Archive v01.n175
On Thu, 29 Jan 1998, Tom Suit wrote:
> Yes, but you said it was "ridiculous". That kind of statement suggests that
> there is evidence to the contrary.
There is.
> Personally, I'm suspicious of it as bones
> are largely calcium, not carbon.
Depends on the sample and the assay.
Kal
=========================================================================
From: Tom Suit <tsuit@UU.NET>
Subject: Re: Re[2]: C37-The FAQ's
Date: Thu, 29 Jan 1998 12:22:44 -0600
Source: Sound Digest Archive v01.n175
At 10:49 AM 1/29/98 -0500, Kalman Rubinson wrote:
>On Thu, 29 Jan 1998, Tom Suit wrote:
>
>> What evidence is there against it?
>
>That's not how science works. If you propose something that no one has
>seen, thought of or demonstrated before, it is incumbent on you to present
>some evidence.
Ennemoser (sp?) presented *some* evidence. Some of the claims are a bit
much though. If coating objects with it makes them sound better, what the
hell, coat your outer ear with it.
But to my original point, the very definition of "ridiculous" implies
overwhelming evidence against a given idea. When you used it in this
case, I tagged you as being similar to the the type that say parafeed
can't work.
-Tom
=========================================================================
From: Kalman Rubinson <rubinsnk@is2.nyu.edu>
Subject: Re: Re[2]: C37-The FAQ's
Date: Thu, 29 Jan 1998 12:30:24 -0500 (EST)
Source: Sound Digest Archive v01.n175
On Thu, 29 Jan 1998, Tom Suit wrote:
> But to my original point, the very definition of "ridiculous" implies
> overwhelming evidence against a given idea. When you used it in this
> case, I tagged you as being similar to the the type that say parafeed
> can't work.
Aha! You think that I am saying something about whether or not the
application of the glop works or, indeed, does anything. I am not. I
termed as 'ridiculous' a specific statement about the operation of
auditory transduction. For this process, there is much information and
the proposition offered is completely unfounded and at odds with present
data.
Let me tag you as the type who cannot separate a repeatable observation
(use of C37 Lack) from an unfounded justification (auditory spectra and
neural filtering). This is a typical audiophile malady.
Kal
=========================================================================
From: "alfred trower" <sedht@hotmail.com>
Subject: Re: Re[2]: C37-The FAQ's
Date: Thu, 29 Jan 1998 14:53:37 PST
Source: Sound Digest Archive v01.n175
<snip>
Hey, can someone start up a c37 list, that way, only those who care have
to download this crap.
Al
Alfred Trower
Consultant, Client/Server Systems
Supply Chain Specialist
- ----------------------------------
"The higher we soar the smaller we appear to
those who cannot fly." Friedrich Wilhelm Nietzsche
______________________________________________________
Get Your Private, Free Email at http://www.hotmail.com
=========================================================================
From: Tom Suit <tsuit@UU.NET>
Subject: Re: Re[2]: C37-The FAQ's
Date: Thu, 29 Jan 1998 16:10:19 -0600
Source: Sound Digest Archive v01.n175
At 12:30 PM 1/29/98 -0500, Kalman Rubinson wrote:
>On Thu, 29 Jan 1998, Tom Suit wrote:
>
>> But to my original point, the very definition of "ridiculous" implies
>> overwhelming evidence against a given idea. When you used it in this
>> case, I tagged you as being similar to the the type that say parafeed
>> can't work.
>
>Aha! You think that I am saying something about whether or not the
>application of the glop works or, indeed, does anything. I am not. I
>termed as 'ridiculous' a specific statement about the operation of
>auditory transduction. For this process, there is much information and
>the proposition offered is completely unfounded and at odds with present
>data.
So what you are saying is that all the "data" shows that sound that reaches
the nerve inside the ear, after having gone through the mechanical parts
of the ear is *completely* identical to the original sound before it entered
the ear?
- -Tom
PS You can tag me aas whatever the hell you want.
=========================================================================
From: Kalman Rubinson <rubinsnk@is2.nyu.edu>
Subject: Re: Re[2]: C37-The FAQ's
Date: Thu, 29 Jan 1998 16:54:58 -0500 (EST)
Source: Sound Digest Archive v01.n175
On Thu, 29 Jan 1998, Tom Suit wrote:
> So what you are saying is that all the "data" shows that sound that reaches
> the nerve inside the ear, after having gone through the mechanical parts
> of the ear is *completely* identical to the original sound before it entered
> the ear?
Encoded linearly. The point is that the offered explanation doesn't
explain anything and the real-world observations do not prove the
explanation.
> PS You can tag me aas whatever the hell you want.
As fairly you did me.
Kal
=========================================================================
From: Tom Suit <tsuit@UU.NET>
Subject: Re: Re[2]: C37-The FAQ's
Date: Thu, 29 Jan 1998 17:03:37 -0600
Source: Sound Digest Archive v01.n175
At 04:54 PM 1/29/98 -0500, Kalman Rubinson wrote:
>On Thu, 29 Jan 1998, Tom Suit wrote:
>
>> So what you are saying is that all the "data" shows that sound that
reaches
>> the nerve inside the ear, after having gone through the mechanical parts
>> of the ear is *completely* identical to the original sound before it
entered
>> the ear?
>
>Encoded linearly. The point is that the offered explanation doesn't
>explain anything and the real-world observations do not prove the
>explanation.
Encoded linearly? What exactly is being encoded?
-Tom
=========================================================================
From: Kalman Rubinson <rubinsnk@is2.nyu.edu>
Subject: Re: Re[2]: C37-The FAQ's
Date: Thu, 29 Jan 1998 17:07:52 -0500 (EST)
Source: Sound Digest Archive v01.n175
On Thu, 29 Jan 1998, Tom Suit wrote:
> Encoded linearly? What exactly is being encoded?
I'm getting tired of this. Try a standard sensory physiology text and
then see if you find any evidence.
Kal
=========================================================================
From: Tom Suit <tsuit@UU.NET>
Subject: Re: Re[2]: C37-The FAQ's
Date: Thu, 29 Jan 1998 17:20:31 -0600
Source: Sound Digest Archive v01.n175
At 05:07 PM 1/29/98 -0500, Kalman Rubinson wrote:
>On Thu, 29 Jan 1998, Tom Suit wrote:
>
>> Encoded linearly? What exactly is being encoded?
>
>I'm getting tired of this. Try a standard sensory physiology text and
>then see if you find any evidence.
There probably isn't any. If there was, then Ennemoser's theory would
not be new. Whoops, I forgot - everything has already been discovered.
Look, it is known that if you put glasses on someone that inverts the
image they receive, the brain will eventually right the image if the
glasses are worn long enough. So why can't the brain do any data
massaging to information coming from the ear?
- -Tom
=========================================================================
From: Kalman Rubinson <rubinsnk@is2.nyu.edu>
Subject: Re: Re[2]: C37-The FAQ's
Date: Thu, 29 Jan 1998 17:29:35 -0500 (EST)
Source: Sound Digest Archive v01.n175
On Thu, 29 Jan 1998, Tom Suit wrote:
> >I'm getting tired of this. Try a standard sensory physiology text and
> >then see if you find any evidence.
>
> There probably isn't any. If there was, then Ennemoser's theory would
> not be new.
Theories are a dime a dozen, or less.
> Look, it is known that if you put glasses on someone that inverts the
> image they receive, the brain will eventually right the image if the
> glasses are worn long enough. So why can't the brain do any data
> massaging to information coming from the ear?
You are not reading what I said. I never said that the brain does not
massage information. (In fact, that is one of my major interests.) I
said that there is no evidence of a transductional transform that
requires it.
Kal
=========================================================================
From: Kalman Rubinson <rubinsnk@is2.nyu.edu>
Subject: Re: Re[2]: C37-The FAQ's
Date: Thu, 29 Jan 1998 21:38:34 -0500 (EST)
Source: Sound Digest Archive v01.n175
On Thu, 29 Jan 1998, alfred trower wrote:
> Hey, can someone start up a c37 list, that way, only those who care have
> to download this crap.
Great.
Kal
=========================================================================
From: Jonathan Morrison <ppdiva@pipeline.com>
Subject: Re: Re[2]: C37-The FAQ's
Date: Thu, 29 Jan 1998 23:59:03 -0500
Source: Sound Digest Archive v01.n175
At 05:29 PM 1/29/98 -0500, you wrote:
>On Thu, 29 Jan 1998, Tom Suit wrote:
>
>
>> Look, it is known that if you put glasses on someone that inverts the
>> image they receive, the brain will eventually right the image if the
>> glasses are worn long enough. So why can't the brain do any data
>> massaging to information coming from the ear?
>
>You are not reading what I said. I never said that the brain does not
>massage information. (In fact, that is one of my major interests.) I
>said that there is no evidence of a transductional transform that
>requires it.
>
>Kal
>
>
I'd like to separate this discussion into its individual components.
1. I have always heard that the ear is a relatively high distortion device.
Is this true?
2. I have always heard that the brain filters out that distortion to give
us usable info about the outside world. Is this true? (Upon rereading this
it looks like if (1) is true then (2) would have to be true.)
3. I have read that the brain's filters have a certain response that can be
specified relative to digital audio, i.e. that while in digital audio the
distortion increases with rising frequency and lower level (fewer samples
and fewer bits per sample) the brain's filters have exactly the opposite
response, i.e. they are most effective at lower frequencies and higher
levels. Is this true?
4. I am not sure what you mean by "transductional transform." Do you mean
that my questions (1) and (2) are not true, or do you mean that while there
is filtering in the ear/brain system, that filtering cannot be so narrowly
specified as Ennemoser is doing?
If (1) is false why don't people design microphones to better match the
mechanical properties of the ear?
I have always heard the myth that it was the secret varnish that gave
Stradivari and Guarneri their special sound, and have always thought it
smelled a bit of bullshit. I think that that myth is the starting point for
the marketing of C37, although that might just be sour grapes, since I sure
as hell can't afford the stuff. I do think, though, that even if all that I
have heard about the ear/brain system is correct, a universal panacea in
the form of a tuned damping compound seems a bit farfetched. I think that
the advocates of this product are ignoring mechanical impedance- how can
one density and viscosity work on both a Lowther cone and a circuit board?
It also seems to me that if it is based on a specific frequency that people
with perfect pitch might have a different reaction to it than people
without. OTOH, an interlinked polymeric compound encasing a resonant system
(ain't jargon grand?) could increase that system's rigidity and raise or
focus its resonant frequency regardless of that compound's mass.
I do think that a discussion of how we hear and interpret what we hear is
very relevant to this group- I have some questions about distortion and
measurements but they will have to wait until I'm a bit fresher. Ta, JDM
=========================================================================
From: Holger Stein <STEINMUSIC@compuserve.com>
Subject: C37-The Idea and links
Date: Fri, 23 Jan 1998 08:10:54 -0500
Source: Sound Digest Archive v01.n168
Hallo,
There are some news about the "C37" idea I would like to share with the
list.
Joe Roberts did already review it in SP 1, and with the time more and
more people made excellent experiences with one of Ennemoser's most
efficient tools, the C37 Lack.
Here in Europe we get more and more good reviews from Hifi magazines in
France, Austria Holland and Germany, and we are glad to have Norman Tracy
from Audio Crafters Guild in America, who will not only distribute our
Kits, but also Ennemoser's C37 Lack there.
Norman Tracy's Website adress is
http://galstar.com/~ntracy/ACG
The official website of Dieter Ennemoser is: www.geocities.com/Cape
Canaveral/Lab/6645
For those who understand German an interesting adress is
http://www.clockwork.de/hirec/trip.htm
It is the online edition of HiFi and Records Review, and there you also
find lots of information about Ennemoser's C37 Lack.
We are also preparing an own website which will contain our whole program,
but it is still under construction.
Best regards
Holger Stein
STEIN HIFI SYSTEMS
Scharpenberg 64a
D- 45468 Muelheim
Germany
Fon ++49 208 32089
Fax ++49 208 390938
GSM ++49 172 4744254
STEINMUSIC@Compuserve.com
Worldwide distribution for Ennemoser's C37 Lack
and much more...
=========================================================================
From: "Bottlehead" <Bottlehead@prodigy.net>
Subject: Re: C37-The Idea and links
Date: Fri, 23 Jan 1998 08:26:35 -0800
Source: Sound Digest Archive v01.n168
> Hallo,
> There are some news about the "C37" idea I would like to share with the
> list.
I finally got around to trying some of this stuff. Put it on the Whamo
drivers, to help me decide if I want to risk coating my PM2As. Seems to do
what they say it does, in fact we could hear a change for the better even
as the stuff was painted on with the drivers playing. Seems to damp out the
higher resonances a bit. Andy Bartha tells me he found the stuff seals up
any porosity in the Lowther cones, improving the bass loading, and does
much of the same peak taming as the cotton stuffing trick. Tucker borrowed
the bottle, to try the stuff on his Exemplar tweets. When I get it back,
the Lowthers get a paint job...
Too bad it's too thick to spray on with an airbrush.
Hey Norman, have you tried it inside your DAC yet?
Doc B.
=========================================================================
From: el34@juno.com
Subject: Re: C37-The Idea and links
Date: Fri, 23 Jan 1998 15:54:57 -0500
Source: Sound Digest Archive v01.n168
On Fri, 23 Jan 1998 08:10:54 -0500 Holger Stein
<STEINMUSIC@compuserve.com> writes:
>Hallo,
>There are some news about the "C37" idea I would like to share with the
list.
Here is my .02 worth:
You Altec fans MUST try this stuff on your hf diaphragms! It makes a BIG
difference. You can tell it right away even before the stuff is dry. It
takes the metallic edge off resulting in a much more natural sound. I
have tried it with the old style 802D and the new tangerine type drivers.
Works great on both.
A word of caution if you decide to coat the older style drivers, the
clearance between the diaphragm and the phase plug is very small. Use a
light coat, and let it dry for awhile or you will end up gluing them
together. You can use a heavier coat on the back side and the suspension.
Works wonders on arms and pickups too...
=========================================================================
From: "Greg Monfort" <wingracer@email.msn.com>
Subject: Re: C37-The Idea and links
Date: Fri, 23 Jan 1998 22:57:50 -0500
Source: Sound Digest Archive v01.n169
Sounds to me you're overdamping them, especially if you're coating the
suspension, plus on the aluminum diaphragms, I imagine you're adding a
enough mass to lower Fs. I wonder how much it effects impulse and frequency
response.
GM
- -----Original Message-----
>
>You Altec fans MUST try this stuff on your hf diaphragms! It makes a BIG
>difference. You can tell it right away even before the stuff is dry. It
>takes the metallic edge off resulting in a much more natural sound. I
>have tried it with the old style 802D and the new tangerine type drivers.
>Works great on both.
>
>A word of caution if you decide to coat the older style drivers, the
>clearance between the diaphragm and the phase plug is very small. Use a
>light coat, and let it dry for awhile or you will end up gluing them
>together. You can use a heavier coat on the back side and the suspension.
>
>Works wonders on arms and pickups too...
>
>
=========================================================================
From: Thomas Danley <tom@ppci.com>
Subject: Re: C37-The Idea and links
Date: Sat, 24 Jan 1998 08:57:15 -0600
Source: Sound Digest Archive v01.n169
Greg Monfort wrote:
>
> Sounds to me you're overdamping them, especially if you're coating the
> suspension, plus on the aluminum diaphragms, I imagine you're adding a
> enough mass to lower Fs. I wonder how much it effects impulse and frequency
> response.
>
> GM
>
Hi
My thoughts exactly, the odds of a coating making the dome more rigid
or adding other favorable properties without adding unfavorable ones too
is pretty unlikely. Unlike a direct radiator, adding any additional
moving mass to a compression driver radiator also dictates a lower hf
rolloff. The coating afterall does not "know" what properties to add
that would improve a particular dome, cone or tonearm etc.
Without measuring a "before and after" you don't know what its doing.
Tom
=========================================================================
From: "Greg Monfort" <wingracer@email.msn.com>
Subject: Re: C37-The Idea and links
Date: Sat, 24 Jan 1998 11:30:08 -0500
Source: Sound Digest Archive v01.n169
I thought that might be the case. The 'metallic sound' is mostly in the
higher freqs, so this makes sense. A better solution is to XO around 5k to a
sweet sounding tweeter.
GM
- -----Original Message-----
Unlike a direct radiator, adding any additional
>moving mass to a compression driver radiator also dictates a lower hf
>rolloff.
>
>Tom
=========================================================================
From: Norm Luttbeg <nluttbeg@politics.tamu.edu>
Subject: Re: C37-The Idea and links
Date: Mon, 26 Jan 1998 11:57:39 -0600
Source: Sound Digest Archive v01.n171
Wow! Juno's empirical approach to using C37 and his use of his ears
will certainly get the theorists at any cost group going.
Thanks for the comments, Juno.
=========================================================================
From: el34@juno.com
Subject: Re: C37-The Idea and links
Date: Mon, 26 Jan 1998 12:47:02 -0500
Source: Sound Digest Archive v01.n171
On Sat, 24 Jan 1998 08:57:15 -0600 Thomas Danley <tom@ppci.com> writes:
>Greg Monfort wrote:
>>
>> Sounds to me you're overdamping them,
<SNIP>
I'm sure you could come up with a thousand and one scientific reasons why
"it won't work".
>The coating afterall does not "know" what properties to add
>that would improve a particular dome, cone or tonearm etc.
>Without measuring a "before and after" you don't know what its doing.
I DID do a "before and after" and "after" was the clear winner! I don't
have the equipment (other than my ears) to measure speaker parameters
with anyway. Most "measurements" have little correlation to how a speaker
sounds with music in a real setting. I don't know about you, but I don't
sit around in an anechoic chamber listening to test signals!
C37 is one of those thing you just have to try. I was given a kit by a
friend (on this list) who was visiting from Germany. I was skeptical, but
since I had the stuff, I decided to try it. I was biased against it, but
THE STUFF WORKS.
_____________________________________________________________________
You don't need to buy Internet access to use free Internet e-mail.
Get completely free e-mail from Juno at http://www.juno.com
Or call Juno at (800) 654-JUNO [654-5866]
=========================================================================
From: Daniel Normolle <monk@umich.edu>
Subject: Re: C37-The Idea and links
Date: Mon, 26 Jan 1998 15:16:02 -0500
Source: Sound Digest Archive v01.n171
Norm Luttbeg wrote:
> Wow! Juno's empirical approach to using C37 and his use of his ears
> will certainly get the theorists at any cost group going.
OK, I'll bite. I have three questions:
1) Applying this stuff to speaker cones is irreversible, right? So this
is not like swapping a capacitor and, if you don't like it, your're just
out the cost of the capacitor. Doesn't this tend to bias one's
response--you better like it, because that's the way it's gonna be?
2) C37 is a lacquer, isn't it? Offered, no doubt, at an audiophile-approved
price. Has anybody compared the results from this magical compound
to lacquers from the local hardware store? If so, how? If not,
why not?
3) How do you get the C37 out of your ears?
dpn
(whose theories are reasonably priced)
=========================================================================
From: Thomas Danley <tom@ppci.com>
Subject: Re: C37-The Idea and links
Date: Mon, 26 Jan 1998 15:33:17 -0600
Source: Sound Digest Archive v01.n171
Norm Luttbeq wrote:
> Wow! Juno's empirical approach to using C37 and his use of his ears
> will certainly get the theorists at any cost group going.
It is nice he liked the effect, new domes would be expensive.
I don't know about "at any cost" part but I do know there is a
difference between actually knowing what is happening and taking
someones word for it that "it works".
el34@juno.com wrote:
>
> On Sat, 24 Jan 1998 08:57:15 -0600 Thomas Danley <tom@ppci.com> writes:
> >Greg Monfort wrote:
> >>
> >> Sounds to me you're overdamping them,
>
> <SNIP>
>
> I'm sure you could come up with a thousand and one scientific reasons why
> "it won't work".
>
> >The coating afterall does not "know" what properties to add
> >that would improve a particular dome, cone or tonearm etc.
> >Without measuring a "before and after" you don't know what its doing.
>
> I DID do a "before and after" and "after" was the clear winner! I don't
> have the equipment (other than my ears) to measure speaker parameters
> with anyway. Most "measurements" have little correlation to how a speaker
> sounds with music in a real setting. I don't know about you, but I don't
> sit around in an anechoic chamber listening to test signals!
You won't find a reputable driver company that doesn't refine there
products using test equipment and use scientific methods to design them,
the days of designing strictly by ear are long over. Your ears while
sensitive to some things are lousy at others.
If you were more familliar with modern measurment techniques, it is
unlikely you would say" Most "measurements" have little correlation to
how a speaker sounds with music in a real setting.", the first step in
finding out what the driver is doing requires reducing or eliminating
the acoustic clutter that the room introduces to better reveal the
drivers actual performance. If you want to listen to what your speakers
do alone, take them outside and listen to them, most speakers sound
vastly better outside w/o room effects. Likewise the idea of the
anechoic chamber is to reduce the number of things that effect the
speakers performance to make its actual performance more measurable or
audible.
Room effects are unavoidable indoors but also unlikely to be altered by
the application of C-37 to your compression driver domes.
On the other hand, even if it were mixed within the Great Pyramid and
then blessed twice by the Pope, the reality is that adding moving mass
to a compression driver radiator lowers the high frequency corner, there
is simply NO way around that. Similarly, it is unlikely that GOD gave
the product an exemption to the other laws of physics that govern how
things work in other areas as well.
Perhaps in addition to the lower roll off frequency, it luckily added
dampening where some was needed or perhaps the added mass in the center
of the dome increased the magnitude of a major resonance or the change
in front volume due to the thickness of the coating effected the hf
cutoff in some way. Any of these are likely to be audible and perhaps
sound "improved" to an individual but without being able to actually
measure anything all you can say is "I think it works", you don't know
what actually happened or why or even if it actually is more accurate
(IE: do a more faithfull job following the input signal).
The coating afterall does not "know" thru ESP or finite element analysis
what properties to add or subtract that would improve a particular dome,
cone or tonearm etc. Without measuring a "before and after" you simply
don't know what its doing. There is no doubt at all that it does
something, exactly what is the question.
Tom
=========================================================================
From: Thomas Danley <tom@ppci.com>
Subject: Re: C37-The Idea and links
Date: Mon, 26 Jan 1998 20:58:44 -0600
Source: Sound Digest Archive v01.n172
Holger Stein wrote:
>
> Hallo Guys,
> I just read the last comments on C37 Lack, and must say I am very amused.
> It is a very controverse discussion between people who have made practical
> experiences with C37 Lack and others who have some theoretical concepts in
> mind where C37 does not fit.
> Kal for example mentioned that he is of the opinion that the idea behind it
> is weired.
> There are lots of tweaking ideas around, which are more ore less succesful.
> But what about a new idea which does not only work here and there, but
> everywhere?
> OK, from a scientific point of view it is necessary to interpret all
> effects you get in relation to the knowledge achieved by the experiments of
> the past.
> And if something is still working, whereever you use it, are you going to
> burn the inventor or is it necessary to think further, and maybee find some
> new conceps which fit better to reality?
Hi
Do you mean reality as in measured performance or from an engineering
point of view or percieved reality in the eye of the beholder?
Until you measure the effect you in the domain of the later rather than
the former.
I find parts of this amusing also.
I think it is humorous that someone would suggest to all that there
compresion drivers domes are improved by a coating without knowing what
it does to the actual performance.
It is also humorous in light of the fact that aluminum has a thin oxide
coat that prevents paint, epoxy and other things from developing a good
bond even if fully de-greased first.
Makes one wonder how long it will take before it begins to seperate.
Also humorous is the implication that those that actually design or
invent drivers, like my self, may not be familliar with the technical
relationships that govern there operation.
Wouldn't it seem to you that the folks that design and build these
drivers and have established the relationships governing there design
and operation also might have a handle on Reality?
I would be very surprised that in this special case, the addition of
moving mass in the form of a coating does not cause a lower mass roll
off corner for example, there simply are no exemptions to the laws that
govern how things actually work even if to the ear it sounds better.
> I mean if people who started using the Lack on a CD, and finally also treat
> their 80 000DM speakers with great success as they say, it may be they are
> weired.
> But if you ask 100 people who personally made their experience with C37
> Lack, and everybody tells you it is great, should it not inspire you to
> first try it and then see what questions still occur?
Well there are countless people that buy Monk stones, pointy feet, green
magic markers for there CD's, magic power cords, quartz healing
crystals, water magnetizers and on and on, all things that depend
largely or entirely on psychology to have there "effect" out side of
there real design which is to seperate the buyer from there money and
transfre it to the sellers pocket.
With SO much hooey being successfully sold, there is good reason to be
suspicious of things that in the telling "sound too good to be true".
Like they say in physics, "extraordinary claims demand extraordinary
proof". Not to say it can't be, it just takes more than saying so.
> So far, we are going to actualize the C37 website continouesly and also
> answer some of the questions.
> And if somebody really thinks he should try this stuff on whatever a
> project, just let me know to see how we can arrange it.
I would be interested in persuing this, I have built inovative drivers
for 15 years and I am working on a full range driver right now and have
plenty of test equipment to quantify its effects. If it works well it
will be specified in the Bill of materials when it goes into production.
Should you question my voracity, go to
http://patent.womplex.ibm.com/
pick advanced text search and under inventor, put Danley Thomas and
search. This will list some of the things I have developed.
Best regards,
Thomas Danley
=========================================================================
From: "Bottlehead" <Bottlehead@prodigy.net>
Subject: Re: C37-The Idea and links
Date: Mon, 26 Jan 1998 21:39:12 -0800
Source: Sound Digest Archive v01.n172
> 2) C37 is a lacquer, isn't it? Offered, no doubt, at an
audiophile-approved
> price. Has anybody compared the results from this magical compound
> to lacquers from the local hardware store? If so, how? If not,
> why not?
Well, it sure doesn't smell the like the nasty nitrocellulose stuff I used
to spray on radio cabinets. It actually smells kinda good. Especially the
third or fourth bottle, which I usually share with that big pink rabbit
that starts hanging around the shop about then.
I think it probably has some other stuff in it. It has an almost citrus
smell to it, and is rather mild compared to the fierce top fueler smell
straight lacquer has. Almost like somebody put a little orange blossom
honey in it.
Doc B.
=========================================================================
From: Holger Stein <STEINMUSIC@compuserve.com>
Subject: Re: C37-The Idea and links
Date: Tue, 27 Jan 1998 04:47:07 -0500
Source: Sound Digest Archive v01.n172
Hallo Thomas,
I regard physics as the art of describing real world phenomens by the aid of mathematics, and I do n
ot want to say that everything invented until now is worth nothing.
What I would like to say is that the mass added by coating a diaphragm is not the reason for the gre
at audiable improvement.
The coating is very thin and long term stable, and although it will add a small amount of mass it wi
ll not significantly change HF rolloff if applied thin.
It is also my opinion that a lot of stuff is sold which brings questionable results, not to say is p
erfectly marketed nonsense where the world does not need more from.
I will look if we can make a limited special offer for those who are not only in the list to show wh
at they have learned but are also interested to widen their horizon of experience.
Have to talk about this with Norman (where are you?), who is able to distribute the stuff.
To Doc B.:
Greetings to your pink rabbit, but are you sure you talk about C37 Lack and not Tequila?
OK, C37 Lack is entirely made of natural ingredients, anyway I would not drink it...
Roberts explanation about how C37 works is quite good, here some frequently asked questions answere
d by Mr. Ennemoser himself:
For those who are interested in further information as Greg, please refer to www.geocities.com/Cape
Canaveral/Lab/6645
FAQŽs January 1998
1. Does C37 Lack dampen the sound (treble-rolloff) and therefore soften ist?
No, dampening would cause plastic sound. Dampening deteriorates solution, and
precise solution ist nessessary to reprocuce complex timbres like that of wood.
C37 Lack shifts the decay-spectrum peaks to frequencies synchronous to those
produced by the ear itself due to itŽs material. Brain cancels out these intrinsic
decaying frequencies to hear whatŽs happening outside the ear, not what concert
is going on inside the ear.
To this topic see also my book the character of sound chapter The Effect of
Dampening and the article in DER STANDARD 16.1.1998.
(If you really want to dampen your speakers, use plastic coating, itŽs much
cheaper!!!)
2. Does the added mass change the sound of the drivers?
The effect of the added mass of the C37 Lack (it is very leightweighted and thin)
is neglectable compared with the benefits to soundquality it adds. This is also
the experience of engineers of ALR JORDAN, SCANSPEAK and TANNOY.
3. Does the sequence of C37 frequencies support a new musical scale?
I would not think so, because
a) musical notes are a complexe mixtures of frequencies and
b) the C37 frequencies show impedance peaks rather than linear distortion
(frequency response peaks).
c) the C37 impedances and therefore phasemodulations have their influence on any
scale, wether exotic
or not, be it noise or sound.
4. Is Ennemoser the most out of control violinmaker, incapable of comprehending
physical laws, but fancying weird theories?
I finished an engineering education at the HTL Innsbruck and did 6 years of
practical soundengineering at a radiostation and a filmproduction. (Physical
education shows you the borders of contemporary physics when you seriously deal
with acoustic phenomenas of instruments and loudspeakers. I am telling this to
people who repeat themselves in proudly pronouncing beeing engineers or
physicists).
I learned violinmaking in Mittenwald and have a journeymanŽs certificate, I am no
amateur. I did research on each of the 150 Instrumetnts I built, and I listen to
natural sounds when playing the violin twice a week in real orchestras. By means
of this pragmatic way I contrived the C37Theory and not by chatting about
fragments of parameters. I pragmatically earn my living by making new instruments
since 20 years.
Dieter Ennemoser
=========================================================================
From: Robert Jorgensen <robert.jorgensen@advalvas.be>
Subject: Re: C37-The Idea and links
Date: Tue, 27 Jan 1998 08:55:14 +0100
Source: Sound Digest Archive v01.n172
Tom,
It might be good to re-cap the ideas behind C37. I'll see if I can dig up
the old posts doing so, but very briefly here.
Enemoser, who is the inventor, is an instrumentmaker and as such concerned
with how laquer controls the sound of the instruments he builds. He came
up with the idea that a certain resonance pattern, corresponding to that of
carbon at 37 degrees centigrade (pretty close to that of us humans) seems
very attractive to listen to. The laquer is an attempt to overlay the
resonance patterns of other materials with one more sympathetic to the
human ear. If this misrepresents C37 I'm sure Holger will correct me.
Of course one can't completely count out other more conventional damping
effects. I have not myself experimented with C37. I would like to, but
also very much appreciate your findings.
Greetings from Brussels (the coldest morning of the new year they say)
Robert Jorgensen
Robert.Jorgensen@advalvas.be
=========================================================================
From: Martin Needleman <mrndlmn@beast.toad.net>
Subject: Re: C37-The Idea and links
Date: Tue, 27 Jan 1998 10:30:48 -0500 (EST)
Source: Sound Digest Archive v01.n173
The most effective way to use C37 is to paint it directly on your ears.
mrn
On Mon, 26 Jan 1998, Norm Luttbeg wrote:
> Wow! Juno's empirical approach to using C37 and his use of his ears
> will certainly get the theorists at any cost group going.
>
> Thanks for the comments, Juno.
>
=========================================================================
From: Norm Luttbeg <nluttbeg@politics.tamu.edu>
Subject: Re: C37-The Idea and links
Date: Tue, 27 Jan 1998 11:18:15 -0600
Source: Sound Digest Archive v01.n173
Given the theory as to why C37 works, the obvious way to deal with the
problem is to remove all your bones.
Martin Needleman wrote:
>
> The most effective way to use C37 is to paint it directly on your ears.
> mrn
>
> On Mon, 26 Jan 1998, Norm Luttbeg wrote:
>
> > Wow! Juno's empirical approach to using C37 and his use of his ears
> > will certainly get the theorists at any cost group going.
> >
> > Thanks for the comments, Juno.
> >
=========================================================================
From: An-shyang Chu <achu@sandia.gov>
Subject: C4S 2nd time
Date: 19 Mar 1998 14:54:43 -0700
Source: Sound Digest Archive v01.n222
HI Joes,
Try 12AT7, 5965 and 396A with Doc/Camille's C4S in the front end of my 2A3
Baby'O during the past few days. The current is set for ~ 8mA and bias at ~2V
for all three. The final plate voltages are depending on the tubes (via C4S
loading).
5965: good image and details, edgy at times, a bit more pace than 12AT7 (not by
much though)
12AT7: a bit tuby and romantic, forgiving but good (I can see why people keep
using this)
396A (=2C51, 5670): great speed and pace, excellent image and details, extend
high and very-very-very low distortions (did not notice this in my amp until
trying out this tube) This is a great tube and up there with 417A in my book.
I would like to know other people's experiences with this little baby!!
next in line: 6BN4A, 8532, 955 and 417A (=5842Q)
hopper
=========================================================================
From: tubesguy@mail.execpc.com (Patrick Currie)
Subject: C4S explanation?
Date: Sat, 2 May 1998 21:32:22 -0500
Source: Sound Digest Archive v01.n267
Doc and others who have C4S experience:
I give up. I must confess my total inability to figure out how to implement
the Camille C4S boards. I think I understand how to choose R1 and R2,
based on the instructions that came with the boards and the Bluesmaster
series. R1 sets the current, and R2 biases the LEDs at 2ma, dependent on
the supply voltage. Fine and dandy.
What, however, determines what voltage is on the plate of the tube? The
Bluesmaster has 200v on the plate of the driver tube, from a supply of
280v. Doc's recent post regarding the parafeed potato amp says to put 160v
on the plate, from a 300v supply. I have not been able to figure out how
the resistor choices and the supply voltage combine to set the plate
voltage.
Could someone briefly tell me how the dang things work? TIA - Pat, at sea
once again
Pat Currie (tubesguy@execpc.com)
=========================================================================
From: "Doc B." <bottlehead@silverlink.net>
Subject: Re: C4S explanation?
Date: Sun, 3 May 1998 07:57:37 -0700
Source: Sound Digest Archive v01.n267
Pat,
You're three quarters of the way there.
R1 is setting the current, and holding it, right? You've also chosen your B+
and have set the LED bias for the given B+ voltage.
Along with that you have put a load of beau coup ohms on top of the plate,
so the supply voltage doesn't really figure in to the determination of the
plate voltage. The B+ just needs to be high enough to let the tube swing to
it's full output, i.e., if the plate is at 160V and the signal needs to
swing another 80V, you need at least a 240V B+.
So in general, the only variable left to play with that will affect the
plate voltage is the cathode resistor value. As you alter its value, varying
the bias, you will affect the plate voltage.
This is why I was vague about the cathode resistor value in my
paraspudphonamp post.
You will want to look at the curves for the 417A to determine the proper
grid bias for an operating point of 20 mA at 160V, or whatever op point you
choose to use.
Divide the grid bias voltage, acquired from the curve, by the current that
you have set with R1, i.e., 1.5V/.020A.
(these are bogus numbers, just for example, use the curves to get the proper
bias voltage) Put a cathode resistor of the resulting value, don't forget to
figure the dissipation of the resistor too, and size it properly. Since the
current is constant, now you have set the grid bias 'constant', and the
plate voltage should pull to the proper value.
This makes for a pretty cool trick, really.
If you don't know the proper grid bias, you can plug in different values and
see which way it pulls the plate voltage. When you get the plate voltage
spec'd for a given plate current, you have hit the right cathode resistor
value.
I used this technique to find an operating point for these obscure 7719s I
was using in a preamp. Couldn't find curves anywhere, so I picked a plate
voltage and a current based on a suggested op point and the max dissipation.
Next I set up the load and the LED bias for the B+ I decided to use, and
plugged the tube in, with an arbritrary cathode resistor that I thought
would put me in the ball park. From there I kept adjusting the cathode
resistor value until I got to my design plate voltage.
We've got a meeting today so I won't be available for questions - should be
way cool, LynnO showed up last night with his PP VV32 amps, I have finally
thrown together a nice beefy low DCR and oily cap L-C-L-C dual mono supply
for the VV52 amp, and Tucker is bringing two new preamp circuits, one SE
parafeed, one SE active loaded cathode follower. We'll also put together a
differential PP parafeed line stage, and shoot off SS shunt regs vs. VR
tube, and 5965 vs. WE 395A/5670/2C51. Got a CD of the band (Paul deLay) we
have tentatively booked for VSAC 98 too, for the gang to audition.
Call me tomorrow if you're still having trouble with the loads.
Doc B.
Doc B.
VALVE
coming soon - www.bottlehead.com
- -----Original Message-----
From: Patrick Currie <tubesguy@mail.execpc.com>
To: sound@deliverator.io.com <sound@deliverator.io.com>
Date: Saturday, May 02, 1998 8:28 PM
Subject: C4S explanation?
>Doc and others who have C4S experience:
>
>I give up. I must confess my total inability to figure out how to implement
>the Camille C4S boards. I think I understand how to choose R1 and R2,
>based on the instructions that came with the boards and the Bluesmaster
>series. R1 sets the current, and R2 biases the LEDs at 2ma, dependent on
>the supply voltage. Fine and dandy.
>
>What, however, determines what voltage is on the plate of the tube? The
>Bluesmaster has 200v on the plate of the driver tube, from a supply of
>280v. Doc's recent post regarding the parafeed potato amp says to put 160v
>on the plate, from a 300v supply. I have not been able to figure out how
>the resistor choices and the supply voltage combine to set the plate
>voltage.
>
>Could someone briefly tell me how the dang things work? TIA - Pat, at sea
>once again
>
>Pat Currie (tubesguy@execpc.com)
>
>
>
=========================================================================
From: tubesguy@mail.execpc.com (Patrick Currie)
Subject: Re: C4S explanation?
Date: Sun, 3 May 1998 10:30:32 -0500
Source: Sound Digest Archive v01.n267
>This makes for a pretty cool trick, really.
>If you don't know the proper grid bias, you can plug in different values and
>see which way it pulls the plate voltage. When you get the plate voltage
>spec'd for a given plate current, you have hit the right cathode resistor
>value.
>We've got a meeting today so I won't be available for questions
>
>Doc B.
No questions remain, buddy. This is a cool trick indeed. I was actually
about seven-eigths there when I asked the question, since I had added a
question about the cathode resistor, and when I did, it kind of suggested
this answer. Of course, if it was totally wrong, I would have looked like
a total idiot (no snickering out there) so I had deleted it.
This was more than theoretical. While I'm working on the parafeed 845
(Paradildo?) I'm going to redo the spud amp with the C4S and a 25k volume
pot, in place of the 100H choke and 100k pot that I'm using now. Appreciate
the help, again. - Pat
Pat Currie (tubesguy@execpc.com)
=========================================================================
From: An-shyang Chu <achu@sandia.gov>
Subject: C4S first impressions
Date: 16 Mar 1998 10:21:58 -0700
Source: Sound Digest Archive v01.n218
Hi Joes,
Got excited by Doc's Blues Master and went ahead put the C4S active load into my
Baby'O last night (between cooking a pot of stew meat, taking care of a 4.5
month old who has the Blues, arranging baby sitting for the weekend, talking to
my wife about her dad etc..) It ONLY took 5 hrs (should have it done within 1/2
hr, right!) and got it to work the first try (amazed myself).
The active load is set for 8.3 mA (0.95V/115ohm ~ 8.3 mA) and the active load
bias is 315 V using the same HV tap from the 2A3s (using two 332K in parallel
for the diodes). The tube is 5965 and the final plate voltages for the two
channels are 163V and 173V with the same 2.2 V bias at the cathodes (the true
current is ~ 8.8 mA). The bias headroom for the output is then ~ 150V (it is
over kill for the 2.2Vx47~104V swing but it is still safe for the MJE530) This
stage is cap-coupled into the parallel-feed 2A3.
I only have about 20 min last night (softly playing CD) and this morning (NPR
over the radio) to listen to it and so these are just the first impressions:
better speed and lower background. One thing that really stand out is the
background... I notice the changes in takes, studio sounds, and switchings
through the radio way better than before. The voices have more body to them
too. There is however a slight haze over everything (over the background).
This might due to the 1/8 watt CC resistors in the cathodes and current settings
(will change them to 1/4 watt metal film tonight) Or maybe I am running the
5965 too hard?? Low level listing is more relaxed as well. Will report more
later.
Some of the line ups for easy eXperimenting: 396A (=5670, 2C51), 417A (=5842),
and 8532. Any others? better operation points for 5965?
hopper
p.s. Doc! nice work.
=========================================================================
From: Michael Hsu <mcwhsu@worldnet.att.net>
Subject: C4S resend of first section
Date: Sun, 02 Aug 1998 13:09:23 -0700
Source: Sound Digest Archive v01.n373
Hey gang,
I am trying to convert my 45 pf amps to the ccs but just can't seem to
get it right. I am using the C4S circuit from the Blues Master direct
coupled to the 45. I am using the CV378 for slow turn-on.
I get 150V at the top of the C4S but it only drops 10V or so to 138V.
I get the 150V using dropping resistors instead of tying it to the 45
cathode. The 5965 is pulling about 10ma. This leads to a 250V, 40ma,
- -45V operating point for the 45; rather than the 275V, 35ma, -55V I was
expecting to get.
One amp seems to play fine but the other has some serious distortion
(even though the voltages measure the same) depending on the 5965
installed. With some 5965s there is a slight midrange distortion but
with others the distortion is significant across the board.
I hope I didn't hook up the transistors backwards or something. The two
LEDs light up. Here's how I read the layout:
For the 2N2907 in the TO-39 package I have (from left to right):
collector, base, emitter (nearest to the tab).
For the MJE350 in the TO-126 package I have (with the collector tab
facing up and from left to right): base, collector, emitter.
Have been scratching my head for a week now......what's
wrong........help...... :-(
Thanks Michael
=========================================================================
From: Michael Hsu <mcwhsu@worldnet.att.net>
Subject: Re: C4S resend of first section
Date: Sun, 02 Aug 1998 15:54:02 -0700
Source: Sound Digest Archive v01.n373
Thanks very much for your comments Grover.
I measured the voltages of the 5965s that didn't work and the voltage at top
of the C4S is the same as the voltage on the plate. Now I understand where
the distortion is coming from (no load). The best V drop I can get is ten
volts - which means I get very little power out before distortion.
Why does it not 'fire.' Regardless of the 5965, I still get the 10ma draw
through the tube - so the current is there.... What are some of the tweeks to
make it foolproof?
I'll probably change to a simple resistor load - and lose a lot of gain. I am
building this for a friend so minimum maintenance is required.....
Thanks and cheers, Michael
=========================================================================
From: Grover Gardner <groverg@postoffice.att.net>
Subject: Re: C4S resend of first section
Date: Sun, 2 Aug 1998 18:06:37 -0500
Source: Sound Digest Archive v01.n373
At 1:09 PM -0700 8/2/98, Michael Hsu wrote:
>Hey gang,
>
>I am trying to convert my 45 pf amps to the ccs but just can't seem to
>get it right. I am using the C4S circuit from the Blues Master direct
>coupled to the 45. I am using the CV378 for slow turn-on.
>
>I get 150V at the top of the C4S but it only drops 10V or so to 138V.
>I get the 150V using dropping resistors instead of tying it to the 45
>cathode. The 5965 is pulling about 10ma. This leads to a 250V, 40ma,
>-45V operating point for the 45; rather than the 275V, 35ma, -55V I was
>expecting to get.
>
>One amp seems to play fine but the other has some serious distortion
>(even though the voltages measure the same) depending on the 5965
>installed. With some 5965s there is a slight midrange distortion but
>with others the distortion is significant across the board.
I had this problem with 417As when I tried them with the early version of
the CCS. I think the problem is that some samples don't quite get up to
bias, and the tube *must* be pulling the amount of current you set the CCs
for in order for it (the CCS) to kick in. Otherwise it's providing no or
inadequate load--no sound or distorted sound. However you do this in your
circuit, you have to tweak the input tube to make sure it's drawing the
required current through the CCS.
You are getting less plate voltage and more current through the 45
presumably because you are adding 5mA or whatever to it's cathode, no?
Grover Gardner
groverg@postoffice.att.net
=========================================================================
From: Grover Gardner <groverg@postoffice.att.net>
Subject: Re: C4S resend of first section
Date: Sun, 2 Aug 1998 23:15:55 -0500
Source: Sound Digest Archive v01.n373
At 3:54 PM -0700 8/2/98, Michael Hsu wrote:
>Thanks very much for your comments Grover.
>
>I measured the voltages of the 5965s that didn't work and the voltage at top
>of the C4S is the same as the voltage on the plate. Now I understand where
>the distortion is coming from (no load). The best V drop I can get is ten
>volts - which means I get very little power out before distortion.
>
>Why does it not 'fire.' Regardless of the 5965, I still get the 10ma draw
>through the tube - so the current is there.... What are some of the tweeks to
>make it foolproof?
Just be sure you have enough voltage for the rms swing you want from the
5965, I think that's all.
>
>I'll probably change to a simple resistor load - and lose a lot of gain. I am
>building this for a friend so minimum maintenance is required.....
>
>Thanks and cheers, Michael
Well, hold on. Couldn't you run the 5965 at 100 volts, and put 150 on the
top of the CCS? That would work, no? 100 volts for 5965, coupled to grid
of 45, that's 156 on the cathode of the 45 and about 460 volts on the
plate--is that right? Then you get some extra current draw on the 45
cathode from the CCS, so just up your total B+ maybe 20 volts to 480 to
compensate and you should be okay.
If this isn't feasible then I guess you could switch to a resistor load.
Keep the direct-coupling but be sure to put 33K/3W resistor between top of
45 cathode resistor and top of 5965 plate load, a la Lofton-white--this
really improves the direct-coupled sound.
Grover Gardner
groverg@postoffice.att.net
=========================================================================
From: Paolo Del Giusto <paolo.delgiusto@studioidea.it>
Subject: CA225 informations, thanks
Date: Fri, 15 Jan 1999 17:23:42 +0100
Source: Sound Digest Archive v01.n578
Hi people,
thank you all for the informations regarding the CA225 chip: it will be
very difficult to find some informations about it, because I'm not sure it
exist..... I don't have the amp in my hands now, I have only a very old
schematic, where CA225 can mean everything. It seems it has 28 pins!
However other IC on the schematic are labeled in the right way, say LM833
or similar.
Again, thank you all, and have a nice week end.
- ------------------------------------------
- ------------Paolo Del Giusto--------------
- ------------------------------------------
- ------paolo.delgiusto@studioidea.it-------
- ------------------------------------------
- ----paolo.delgiusto@elettra.trieste.it----
- ------------------------------------------
=========================================================================
From: Philippe <Cadique@worldnet.fr>
Subject: Cabasse and tube amp
Date: Mon, 25 May 1998 12:48:03 +0200
Source: Sound Digest Archive v01.n291
Hi sounds lovers
My father gave me old (20 years) cabasse speakers. This is a 3 ways
enclosure with 30 cm bass speaker with medium and tweeter.
I don't know the type, there is only type 310 and a serial number on the
back. Does any one know those speakers ?
I would like to go for a tube amp.
But with the very bad efficiency of the cabasse (with my solid state
amplifier 80W I've to push the volume a lot to get a good level) I don't
know if it's a good idea.
I visited 15 days ago an hight end sound addict. He had Onken enclosure
with Altec speakers, TAD horn and Fostex tweeter. The amplifier was a
300B SE tube amp delivering 7W ! with a passive preamp. The sound was
amazing and very powerfull. This guy told me that if I want to go for
tube amplification I had to use very efficients speakers to get a good
level (this is another philosophy in front of solid state man ...).
So is there a good way to solve my problem.
Philippe Camus
=========================================================================
From: "Le Cleac'h J.-M." <lecleach@cgi.ensmp.fr>
Subject: Re: Cabasse and tube amp
Date: Mon, 25 May 1998 17:14:32 +0200
Source: Sound Digest Archive v01.n291
- ----------
> De : Philippe <Cadique@worldnet.fr>
> A : sound@deliverator.io.com
> Objet : Cabasse and tube amp
> Date : lundi 25 mai 1998 12:48
>
> Hi sounds lovers
>
> My father gave me old (20 years) cabasse speakers. This is a 3 ways
> enclosure with 30 cm bass speaker with medium and tweeter.
> I don't know the type, there is only type 310 and a serial number on the
> back. Does any one know those speakers ?
> I would like to go for a tube amp.
> But with the very bad efficiency of the cabasse (with my solid state
> amplifier 80W I've to push the volume a lot to get a good level) I don't
> know if it's a good idea.
Hello Philippe,
In my bedroom I use a pair of Cabasse Clipper 312 and probably your
reference is for an older but not so older Cabasse Clipper.
Efficiency of the Cabasse Clipper is 94 - 95 dB/1W/1m.
The 30cm driver is probably the 30BZ18,I use that driver in a modified
Petite Onken (150 liters) of my own. I yet spoke about that enclosure on
the Joenet, and few friends from the Joenet who visited me have reported
also the results I obtain with it.
> I visited 15 days ago an hight end sound addict. He had Onken enclosure
> with Altec speakers, TAD horn and Fostex tweeter. The amplifier was a
> 300B SE tube amp delivering 7W ! with a passive preamp. The sound was
> amazing and very powerfull. This guy told me that if I want to go for
> tube amplification I had to use very efficients speakers to get a good
> level (this is another philosophy in front of solid state man ...).
Don't worry about the Cabasse, they are a perfect fit with tube amplifiers.
I used my modified Onken during 10 years with tube amplifiers (at the
moment as my system is multiamplied, I use them with a 28 watts class A
Hiraga SS amplifier).
If you don't want to build big bass enclosure with those driver, I
recommand to you to modify the Clipper(closed enclosures) to make them
bass-reflex. 2 holes of 65mm at the bottom of the front face give a good
tuning. If you want go lower than 40Hz in the bass, you have to rebuild a
larger enclosure. If you want to sell your drivers, tell me, mine are
15years old and it could be interesting for me to have another pair. more
recent version of the Clipper use the 30M20, which one is excellent also,
nearly the same Thiele and Small parameters than the 30BZ18.
Best regards,
Jean-Michel Le Cleac'h, paris, France*
=========================================================================
From: Philippe <Cadique@worldnet.fr>
Subject: Re: Cabasse and tube amp
Date: Tue, 26 May 1998 11:01:52 +0200
Source: Sound Digest Archive v01.n292
Le Cleac'h J.-M. wrote:
> Hello Philippe,
>
> In my bedroom I use a pair of Cabasse Clipper 312 and probably your
> reference is for an older but not so older Cabasse Clipper.
> Efficiency of the Cabasse Clipper is 94 - 95 dB/1W/1m.
> The 30cm driver is probably the 30BZ18.
I opened the Cabasse this morning and the speakers are referenced:
Bass : Cabasse electroacoustic France 30-12
Medium : Type 12-16 (in a self enclosure).
Tweeter: TWM3
> I use that driver in a modified
> Petite Onken (150 liters) of my own. I yet spoke about that enclosure on
> the Joenet, and few friends from the Joenet who visited me have reported
> also the results I obtain with it.
Do you mean that you use other speakers for medium and tweeter (Horns ?)
> Don't worry about the Cabasse, they are a perfect fit with tube amplifiers.
> I used my modified Onken during 10 years with tube amplifiers (at the
> moment as my system is multiamplied, I use them with a 28 watts class A
> Hiraga SS amplifier).
Ok, so I go for it.
As I own electronic equipment (Osciloscope, frequency meter, Bruel and
kjoer voltmeter, etc...)
and as I design my PCB with CAO system, I would like to build the
amplifier by myself.
An old engineer gave me a box full of tube (old but never used):
EL34, 6L6, EL84, ECC 81-82-83 (Telefunken, Mazda, Philips, Siemens) and
also TV tubes.
I know on joenet you don't like so much those tubes, but as I want to
save money and as it's my first experience in tube amp I prefer to use
it.
The French revue LED published some months ago an 8xEL84 class A
amplifier (octuor), they advice to use Chretien or ACEA output
transformer, maybe there is a better choice ?
> If you don't want to build big bass enclosure with those driver, I
> recommand to you to modify the Clipper(closed enclosures) to make them
> bass-reflex. 2 holes of 65mm at the bottom of the front face give a good
> tuning. If you want go lower than 40Hz in the bass, you have to rebuild a
> larger enclosure.
I think it's a good idea.
I'll try this in the future.
> If you want to sell your drivers, tell me, mine are
> 15years old and it could be interesting for me to have another pair. more
> recent version of the Clipper use the 30M20, which one is excellent also,
> nearly the same Thiele and Small parameters than the 30BZ18.
Each time I sell an audio stuff I always regret .....
If my memory serve you advice us some months ago for triodemania 98,
sadly I miss it.
If they do it again please tell it on joenet.
Jim wrote
> The only other thing that
> I might add is that you have heard probally one great system and may be only
> satified with having the high end addicts system so if you buy or build one like
> it you would probally save money in the long run.
My goal is to save money now :=(
Thank you very much for your very good advice, and long life to joenet.
Philippe Camus
=========================================================================
From: Grover Gardner <groverg@postoffice.att.net>
Subject: Re: Cabasse and tube amp
Date: Tue, 26 May 1998 08:24:00 -0500
Source: Sound Digest Archive v01.n293
At 11:01 AM +0200 5/26/98, Philippe wrote:
>Ok, so I go for it.
>As I own electronic equipment (Osciloscope, frequency meter, Bruel and
>kjoer voltmeter, etc...)
>and as I design my PCB with CAO system, I would like to build the
>amplifier by myself.
>An old engineer gave me a box full of tube (old but never used):
>EL34, 6L6, EL84, ECC 81-82-83 (Telefunken, Mazda, Philips, Siemens) and
>also TV tubes.
>I know on joenet you don't like so much those tubes, but as I want to
>save money and as it's my first experience in tube amp I prefer to use
>it.
Ahem! At the risk of speaking for the group as a whole, we like all tubes
here! :-)
>The French revue LED published some months ago an 8xEL84 class A
>amplifier (octuor), they advice to use Chretien or ACEA output
>transformer, maybe there is a better choice ?
Depending on how much power you need, any of the above tubes would make a
fine starter amp. The EL84 is a really pretty tube, especially. Since
it's a first project, perhaps you could build a very simple ECC81/EL84
push-pull amp? There are a number of very easy Mullard-type circuits
available, the parts would be very cheap and the sound would be hard to
beat. I don't know the circuit you mention, but it would be a good option.
VTL made a very lovely push-pull-parallel EL84 amp here that sounded
extremely good.
Grover
=========================================================================
From: "Le Cleac'h J.-M." <lecleach@cgi.ensmp.fr>
Subject: Cabasse carbone membrane compression driver (for military purpose...)
Date: Mon, 30 Nov 1998 17:21:11 +0100
Source: Sound Digest Archive v01.n509
Hello,
Cabasse loudspeakers equipped the new nuclear propulsed french ship
"Charles de Gaulle".
There is on Cabsse's website some informations about the horn loaded
compression drivers with carbon membrane they specially designed for that
ship.
Text is in french, but for those who cannot read it, pictures are
intersting anyway...
http://www.cabasse.com/rp/cabrpcdg.htm
http://www.cabasse.com/rp/cabrpcd1.htm
http://www.cabasse.com/rp/cabrphpc.htm (pictures)
Best regards,
Jean-Michel Le Cleac'h
=========================================================================
From: "George Powell" <george_t_powell@smb.com>
Subject: Cabinets for triaxial Speakers
Date: Tue, 13 Jan 1998 18:21:34 -0400
Source: Sound Digest Archive v01.n160
I just brought a pair of ElectroVoice 12trxb drivers and I looking for a
cabinet design. The Crofton CLASSIC COAX STUDIO REFERENCE MONITORS,
(http://users.fastrans.net/classicaudio/othrspk.html) look like a good
deal but whose has heard of the company or the cabinet. I like the
sound of QUAD ESL's (who doesn't) but I want the efficiency and power.
I fell in love with SET, when I heard Don Gaber's setup at his old shop,
Fi. Living in Brooklyn doesn't give me the space for A-7 and I can't
afford Lowthers.
What's out there in cabinet designs or software design code. I am
looking for a nice tower with a narrow baffle. With triaxial and
coaxial speakers which is better Bass Reflex or Closed Box? Can you do
Tranmission line?
george
p.s. Anybody know any good cabinetmakers?
- --
______________________________________________________________________________
Salomon Smith Barney | EMAIL: George_Powell@smb.com
Capital Markets PC\Novell Operations | VOICE:(212) 723-5967
390 Greenwich Street | Alpha:(800) 225-0256 pin#(87055)
6th flr West | PAGER:(917) 904-5749
New York, N.Y. 10013 | FAX:(212) 723-8961
"640K ought to be enough for anybody."
---Bill Gates, 1981
_____________________________________________________________________________
=========================================================================
From: Kalman Rubinson <rubinsnk@is2.nyu.edu>
Subject: Re: Cabinets for triaxial Speakers
Date: Tue, 13 Jan 1998 20:51:14 -0500 (EST)
Source: Sound Digest Archive v01.n160
On Tue, 13 Jan 1998, George Powell wrote:
> I just brought a pair of ElectroVoice 12trxb drivers and I looking for a
> cabinet design. The Crofton CLASSIC COAX STUDIO REFERENCE MONITORS,
> (http://users.fastrans.net/classicaudio/othrspk.html) look like a good
> deal but whose has heard of the company or the cabinet. I like the
> sound of QUAD ESL's (who doesn't) but I want the efficiency and power.
> I fell in love with SET, when I heard Don Gaber's setup at his old shop,
> Fi. Living in Brooklyn doesn't give me the space for A-7 and I can't
> afford Lowthers.
Hey, I had A7s when I lived in Brooklyn.
> What's out there in cabinet designs or software design code. I am
> looking for a nice tower with a narrow baffle. With triaxial and
> coaxial speakers which is better Bass Reflex or Closed Box? Can you do
> Tranmission line?
The EVs were designed to be used in reflex or folded horn enclosures.
Kal
=========================================================================
From: Steve Fellini <steve@helix.nih.gov>
Subject: Re: Cabinets for triaxial Speakers
Date: Wed, 14 Jan 1998 08:39:46 -0500 (EST)
Source: Sound Digest Archive v01.n160
From: "George Powell" <george_t_powell@smb.com>
Date: Tue, 13 Jan 1998 18:21:34 -0400
I just brought a pair of ElectroVoice 12trxb drivers and I looking for a
cabinet design. The Crofton CLASSIC COAX STUDIO REFERENCE MONITORS,
(http://users.fastrans.net/classicaudio/othrspk.html) look like a good
deal but whose has heard of the company or the cabinet.
I bought a pair of classic coax cabs a couple of years ago to use with
Altec 601As. They were well made, nice-enough looking and the 601s
sounded very good in them. The price wasn't bad either, if I remember
right.
=========================================================================
From: Carter Hendricks <carterh@crl.com>
Subject: Re: Cabinets for triaxial Speakers
Date: Wed, 14 Jan 1998 11:29:29 -0800 (PST)
Source: Sound Digest Archive v01.n161
On Wed, 14 Jan 1998, George Powell wrote:
> Any chance some one might have plans or a directions on finding some?
I don't think it works that way. I mean, you can't plug in
"triaxial" and get an enclosure design. In my experiments with
the Jensen coax stuff I had to search back in early ['50s] audio
magazines to find what the manufacturers' had suggested. The
Jensen stuff finally fell into my lap courtesy of another list
member. But I think you'll have to hunt for a cabinet design
intended for your specific driver, and even then remember that
development was less "quasi-scientific" than now. Everything
was big, too, think refrigerator-sized footprints. It -is-
out there, but it will be a search. Public Library.
By the way, though I don't mind the rolled-off higher notes from
the simple compression tweeter on my cheapo bottom-of-the line
15 inch Jensen, I haven't liked the penetrating harshness of the
cast aluminum coax/triax Jensens etc*. I mean it's dive over the
couch and cover your ears.
--Carter
* 'haven't heard a 604 or Stephens.
=========================================================================
From: "Daniel J. Marshall" <danmarshall@worldnet.att.net>
Subject: Re: Cabinets for triaxial Speakers
Date: Wed, 14 Jan 1998 11:37:19 -0800
Source: Sound Digest Archive v01.n161
George Powell wrote:
>
> Any chance some one might have plans or a directions on finding some?
>
> --
> ______________________________________________________________________________
> Salomon Smith Barney | EMAIL: George_Powell@smb.com
> Capital Markets PC\Novell Operations | VOICE:(212) 723-5967
> 390 Greenwich Street | Alpha:(800) 225-0256 pin#(87055)
> 6th flr West | PAGER:(917) 904-5749
> New York, N.Y. 10013 | FAX:(212) 723-8961
>
> "640K ought to be enough for anybody."
> ---Bill Gates, 1981
> _____________________________________________________________________________
Well, it so happens that this is one on my pet projects. I have
collected three pairs of older coax speakers and intend to make several
sets of cabinets, most likely duct loaded reflex about 4 ft tall and
about as wide as the speakers, but it may be a while before I get around
to actually starting construction, probably spring.
I have pretty well worked out the constructions details and gathered
bits and pieces to make a plate joiner attachment (also called biscuit
cutter) for an old shopsmith (or drill press). Anyone who has worked
with dowelled joints knows what a pain in the ass they can sometimes be
and I am at a stage of wanting to do something better than screwed/glued
butt joints, but have had my fill of dowelled joints.
Unfortunately the little hand held plate joiners cost about $150 bucks,
which is quite a bit to pay for something that will only be used
occasionally, though they can greatly facilitate cabinetry projects.
I scrounged around and found a replacement "biscuit cutter" blade on
clearance at Home Depot for $13. Using a specially cut flange (these
things have a wierd 27/32 inch [22mm] diameter mounting hole) and a
standard 9/16 shaft-to-1/2 inch thread spindle adaptor, this will
comprise a specialized attachment that can quickly be mounted on the
Shopsmith. Also, will make make a springloaded sliding bed out of MDF,
or whatever, that can be quickly placed over the SS table. Together
this will then comprise a floor model biscuit-joiner-on-the-cheap which
should be more convenient and production oriented than the little hand
held jobbies and will only cost about twenty bucks. I plan to use oak
plywood for the enclosures (cause I already have a couple sheets) and
solid oak corners joined at both intersections by biscuits. By making a
batch of about six cabinets, all similar cuts can be done at one time
thereby minimizing setup time. I glibly prognosticate that by using
this construction technique one should be able to buzz out a set of
cabinets in a few hours. Well, we all know how that goes.
Anyway, that is one of my latest project ideas, for what it's worth.
BTW some of these these old coaxes sound pretty good generally speaking.
So far the ones I have played about with don't do well in the very low
bass range, so if you are a low-bass-freak (like me) you might want to
think about using a subwoofer. This will allow the tower to be a bit
smaller as well. Since I am thinking toward an eventual home theater
setup, the subwoofer sort of goes with the territory anyway.
I would be interested in other's listening impressions of various older
coax speakers and would be willing to share my recent impressions. So
far I have recent experience with the University 312, 312.200, Utah
"Pandorah" (Pan-doh-ray), 8 inch Goodmans 208 triaxioms and some EV
SP12Bs which are full range units, and, of course, the 12 Tannoy Golds.
I do not have any plans currently drawn up, but perhaps will have before
too long, in case you do not find suitable plans elsewhere. This is a
simple enough project that you ought to be able to wing-it alone, I
would think.
Dan Marshall
=========================================================================
From: "George Powell" <george_t_powell@smb.com>
Subject: Re: Cabinets for triaxial Speakers
Date: Wed, 14 Jan 1998 12:32:50 -0400
Source: Sound Digest Archive v01.n161
Any chance some one might have plans or a directions on finding some?
- --
______________________________________________________________________________
Salomon Smith Barney | EMAIL: George_Powell@smb.com
Capital Markets PC\Novell Operations | VOICE:(212) 723-5967
390 Greenwich Street | Alpha:(800) 225-0256 pin#(87055)
6th flr West | PAGER:(917) 904-5749
New York, N.Y. 10013 | FAX:(212) 723-8961
"640K ought to be enough for anybody."
---Bill Gates, 1981
_____________________________________________________________________________
=========================================================================
From: Petter Eneroth <ehp@ffa.se>
Subject: Re: Cabinets for triaxial Speakers
Date: Thu, 15 Jan 1998 10:22:59 +0100
Source: Sound Digest Archive v01.n161
I bought a pair of Goodmans triaxial 12 inch speakers (dont now which
model yet) in their
original enclosures.
It's some kind of variation on bass reflex.
There is an "acustical resistance (some kind of felt material)" in a
square large opening on the
back baffle. I have seen somewhere that this principle is supposed to
broaden the bassreflex
resonance and lower its max resistance value.
I haven't figured out any model name.I would guess they are from the
50's or early
60's. I Badly needed some efficient speakers for my homebrewn 5 watt SE,
no NFB.
Soundwise what is there is pleasant but not much at frequency extremes.
Have been thinking on trying them in open baffles with a subwoofer.
Best regards Petter Eneroth Stockholm Sweden
=========================================================================
From: Kalman Rubinson <rubinsnk@is2.nyu.edu>
Subject: Re: Cabinets for triaxial Speakers
Date: Thu, 15 Jan 1998 11:00:32 -0500 (EST)
Source: Sound Digest Archive v01.n162
On Thu, 15 Jan 1998, Petter Eneroth wrote:
> I bought a pair of Goodmans triaxial 12 inch speakers (dont now which
> model yet) in their
> original enclosures.
>
> It's some kind of variation on bass reflex.
> There is an "acustical resistance (some kind of felt material)" in a
> square large opening on the
> back baffle. I have seen somewhere that this principle is supposed to
> broaden the bassreflex
> resonance and lower its max resistance value.
Goodmans ARU was discussed in the past. Check dejanews. It came and
went as did similar devices from other mfrs.
Kal
=========================================================================
From: Richard C Nevill <rnevill@is.dal.ca>
Subject: Cable Internet Access
Date: Fri, 17 Jul 1998 23:07:01 -0300 (ADT)
Source: Sound Digest Archive v01.n348
HI all,
A while ago I asked the group about us at home switching from a phone
based internet access to a cable based access..
Well the results are in. We wanted to switch because we have a 16 year
old kid at home that is always on the 'phone. This, of course, made it
hard for the rest of us to get on the internet. So. comparing prices, we
came up with this; Phone based internet: $25.95 for 60/hrs/month
$15.95/mon for an extra line
for the kid
equals $41.90/per month
So the cable based internet access costs us $44.95/month. By my reconing
we pay an extra $4.00 dollars a month to have the kid off the phone when
someone want's to play on the internet. Well worth it !
Extra plusses; I've seem download speeds of up to 80/kps, The local
server keeps copies of any site anyone has visited so that when you want
to visist a site all it looks for is updates before it puts it on
your screen, speeding things up alot. Things like a QuickTime video are
there, so soon that you don't worry that it will take some time to
download it and can view it 'right now'. Major cool for someone like me
who likes to view the video clips on the NHRA site are only a couple
seconds away.
The only downside I can see is that sometimes the server is getting
upgraded and at 3 or 4 in the morning I can't get on. Pretty small price
to pay.
So, in conclusion, if your cable company offers a cable connect for an
affordable price, and remember you get unlimited time, I say go for it.
Especially if you have have kid/s.
I like it!
Cheers
Richard Nevill
PS The cable company told us we had to use the MSN or we would have
problems. Well we've been using Netscape 4 for 2 months and NO problems.
So don't believe 'em when they say that
=========================================================================
From: Douglas Purl <dcp@selway.umt.edu>
Subject: Cables and Faeries
Date: Fri, 28 Aug 1998 23:35:26 -0600 (MDT)
Source: Sound Digest Archive v01.n408
One of my son's high-school chums did his EE at U. Wisconsin under R. A.
Greiner and was part of the cable study published in the JAES and also in
Audio. He and I discussed the studies while they were ongoing. Every
effort was made to find positive responses. At the end, Dick Greiner left
the possibility open, but the fundamental results were what one would
expect.
In the early nineties the Boston Audio Society Speaker published an
interesting piece by a fellow whose first job out of college was working
for a large American company that set him loose, with a full array of the
finest test equipment, on a year-and-a-half study checking all manner of
cables, etc., used on ships and in other military communications
equipment. What he discovered is that all physical connectors, of any
type whatever, show varying contact resistance. He found he could unplug
any device and on reconnection, no matter what was done to the connectors,
the results would differ. And float. Study courtesy of your U.S. tax
money.
Makes a fellow wonder about all these Jesuitical distinctions attested to
by folks who plug in something new and experience an epiphany.
Doug Purl
=========================================================================
From: "Ken Dangerfield" <bpyakd@mail.island.net>
Subject: *CAD [off topic]
Date: Mon, 26 Jan 1998 22:14:36 -0800
Source: Sound Digest Archive v01.n172
I have to produce some drawings for the enclosures for the AC
conditioner "gadget" that John Camille designed, so that I can take
them to the shop for laser cutting. Also want to create some
revised drawings for the Lowther Fidelio enclosures to accomodate
thicker panels.
So, I downloaded some CAD shareware (GammaCAD and Delta CAD). What
a singular disappointment. Almost completely lacking in any sense of
intuitivness and also missing many expected time savers. These are
not professional programs - they're designed (I assume) for
private/amateur users like me. Yet they can't perform some of the
basic calculations necessary to do even the simplest drawings and
they don't even provide an on-screen calculater for me to do it.
I would appreciate any recommendations for simple CAD programs that
can do more than layout greeting cards and doghouses (shareware or
purchase doesn't really matter).
TIA and regards,
Ken Dangerfield
=========================================================================
From: davidbarnett@aristotle.net (David N. Barnett)
Subject: Re: *CAD [off topic]
Date: Tue, 27 Jan 1998 06:02:51 GMT
Source: Sound Digest Archive v01.n172
On Mon, 26 Jan 1998 22:14:36 -0800, "Ken Dangerfield"
<bpyakd@mail.island.net> wrote:
>I would appreciate any recommendations for simple CAD programs that
>can do more than layout greeting cards and doghouses (shareware or
>purchase doesn't really matter).
For casual CAD needs, I'd suggest AutoSketch from AutoDesk (the same
guys who make AutoCAD). You can find AutoSketch at most computer
superstores for less than a hundred bucks. It's pretty intuitive to
use, and will do accurate drawings with dimensions and stuff if you
need 'em. If you wanna spend a lot more, there's always AutoCAD LT,
which is slightly less than five hundred bucks, and will do just about
anything that the $4K AutoCAD R14 will do, except that it lacks a
programming language for macros, and is only 2D.
Other possibilities include CorelCADD, a demo copy of which can be
downloaded from the Corel web site (if you've got time for a 5-10M
download...).
- --dnb
=========================================================================
From: Ron Bales <rbales@gte.net>
Subject: Re: *CAD [off topic]
Date: Tue, 27 Jan 1998 08:04:32 -0500
Source: Sound Digest Archive v01.n174
Hi Ken, my favorite among the cheap CAD programs is TurboCAD. You can
pay a lot more and do a lot worse. It does handle DXF files.
ROn
Ken Dangerfield wrote:
>
> I have to produce some drawings for the enclosures for the AC
> conditioner "gadget" that John Camille designed, so that I can take
> them to the shop for laser cutting. Also want to create some
> revised drawings for the Lowther Fidelio enclosures to accomodate
> thicker panels.
>
> So, I downloaded some CAD shareware (GammaCAD and Delta CAD). What
> a singular disappointment. Almost completely lacking in any sense of
> intuitivness and also missing many expected time savers. These are
> not professional programs - they're designed (I assume) for
> private/amateur users like me. Yet they can't perform some of the
> basic calculations necessary to do even the simplest drawings and
> they don't even provide an on-screen calculater for me to do it.
>
> I would appreciate any recommendations for simple CAD programs that
> can do more than layout greeting cards and doghouses (shareware or
> purchase doesn't really matter).
>
> TIA and regards,
> Ken Dangerfield
=========================================================================
From: David Home <tubehead@vcn.bc.ca>
Subject: Calibrated eyeballs
Date: Fri, 5 Sep 1997 13:15:27 -0700 (PDT)
Source: Sound Digest Archive v01.n012
I don't have a distortion meter and wouldn't know how to
use it anyway. I do have a signal generator and a ancient
scope though. My question is this: When observing the waveform
of a sine wave as the amo approches clipping, the first sign of
distortion is a 'bulging' of the peak. This happens before the
peak actually starts to 'flatten'. Can I tell visually what
level of distortion this indicates roughly? In other words,
does the 'bulging' corispond to 2% distortion and the
'flattening to 5%? Or something like that?
Regards, David
=========================================================================
From: Dale.Simon@pscmail.ps.net
Subject: Re: Calibrated eyeballs
Date: Mon, 8 Sep 1997 10:44:00 -0500
Source: Sound Digest Archive v01.n015
Long long ago, I did some distortion analysis using a Tek scope
and a 35mm camera. Once you get the waveform transfered to
graph paper, you can do the FFt manually. Of coarse, that's the
hard way. There are probably share ware programs that could
also do it for you. You will not be as accurate as an FFT
analyzer, but hey!
Dale
______________________________ Reply Separator
_________________________________
Subject: Calibrated eyeballs
Author: owner-sound@LISTS.IO.COM%smtp at x400po
Date: 9/5/97 3:15 PM
I don't have a distortion meter and wouldn't know how to
use it anyway. I do have a signal generator and a ancient
scope though. My question is this: When observing the waveform
of a sine wave as the amo approches clipping, the first sign of
distortion is a 'bulging' of the peak. This happens before the
peak actually starts to 'flatten'. Can I tell visually what
level of distortion this indicates roughly? In other words,
does the 'bulging' corispond to 2% distortion and the
'flattening to 5%? Or something like that?
Regards, David
<Zero length text item>
=========================================================================
From: Kalman Rubinson <rubinsnk@is2.nyu.edu>
Subject: Re: Calibrated eyeballs
Date: Mon, 8 Sep 1997 15:00:02 -0400 (EDT)
Source: Sound Digest Archive v01.n015
On Mon, 8 Sep 1997 Dale.Simon@pscmail.ps.net wrote:
> Long long ago, I did some distortion analysis using a Tek scope
> and a 35mm camera. Once you get the waveform transfered to
> graph paper, you can do the FFt manually. Of coarse, that's the
> hard way. There are probably share ware programs that could
> also do it for you. You will not be as accurate as an FFT
> analyzer, but hey!
There are numerous shareware programs which will do the FFT with your Pc
sound card. The limitation, of course, is the card.
Kal
=========================================================================
From: Peter Sikking <peter.sikking@amc.de>
Subject: Calling all NYC members...
Date: Tue, 31 Mar 1998 15:12:39 +0000
Source: Sound Digest Archive v01.n239
Hi Joesters,
I will be in NYC next week, from the 6th until the 12th.
If any of you wants to show of his system than I would be interrested
to meet up. Also something like a SP-NYC happy hour to meet some faces
behind the names would be terrific.
See you there,
--Peter
music lover, ultra-fi builder, GUI designer & developer, on drums...
from:amsterdam@ulm.germany +49 731 505 1679 facsimile +49 731 505 1808
=========================================================================
From: slagle@dtlweb.com
Subject: calling all parallel feeders
Date: Tue, 9 Dec 1997 21:01:20 -0500 (EST)
Source: Sound Digest Archive v01.n130
I would be interested to hear from all the parallel feed newbies out there
(the veterans as mikey pointed out cut their teeth some 50 years ago) how
much the cap selection effects the sound of the circuit.
first lets consider this a hypothetical cost no object kiss amp...
given the thought that any capacitor will change the sound (drastically
IMLE) it would seem like a good idea, if there had to be a cap to place it
as far downstream in the circuit as possible.... my thinking here is that
an input cap will introduce distortion, which in turn will be amplified by
the following stages, but the cap in a PF setup sees a much higher signal
but its "sound" sees no further amplification....????
I am not personally a big fan of caps anywhere.... any time i have been
able to avoid one, I have preferred the sound... but moving on in
thought...
take a 3 stage amp with tubes 1,2,and 3...
Amp A has 1 directly coupled to 2 with a plate load choke cap coupled to 3
and a gapped output.
Amp B has 1 directly coupled to 2 IT coupled to 3 which is parallel fed..
so there are essentially the same parts in each amp, only their positions
change... it seems to me that amp B would be better on paper, since even
though there is still a cap there, it is further downstream so to speak,
and of course it keeps the DC out of the primary of the output... the
so-called achilles heel of SE...
I guess there are those that can argue that like transformers, it is much
easier to build a cap to handle smaller signals (ie change the sound less)
at which point it becomes that dreaded lesser of two evils... next, all
theory goes out the window and your ears rule the roost.
does anyone out there have opinions of where in a circuit it is best to
hide a cap..or a dc carrying trannie???.. right now i dont have any caps
outside the PS and output cathode bypass... and every time I sneak one in
place of an interstage...(keeping a plate load choke since i don't like
resistors either...only three per amp including the PS (input grid, volume,
output cathode)) anyhoos adding a cap always makes it more audiophile, but
much less enjoyable...
anybody
dave
=========================================================================
From: John Levreault <jlevro@shore.net>
Subject: Re: calling all parallel feeders
Date: Wed, 10 Dec 1997 09:03:17 -0500
Source: Sound Digest Archive v01.n130
At 09:01 PM 12/9/97 -0500, slagle@dtlweb.com wrote:
>
>
>given the thought that any capacitor will change the sound (drastically
>IMLE) it would seem like a good idea, if there had to be a cap to place it
>as far downstream in the circuit as possible.... my thinking here is that
>an input cap will introduce distortion, which in turn will be amplified by
>the following stages, but the cap in a PF setup sees a much higher signal
>but its "sound" sees no further amplification....????
>
>
In fact, the "sound" of the cap in the PF primary will be attenuated by the
step-down ratio of the output tranny.
JL
=========================================================================
From: AirGapped <AirGapped@aol.com>
Subject: Re: calling all parallel feeders
Date: Wed, 10 Dec 1997 09:18:34 EST
Source: Sound Digest Archive v01.n130
In a message dated 97-12-10 02:12:26 EST, the man with the third eye wrote:
> given the thought that any capacitor will change the sound (drastically
>IMLE) it would seem like a good idea, if there had to be a cap to place it
>as far downstream in the circuit as possible.... my thinking here is that
>an input cap will introduce distortion, which in turn will be amplified by
>the following stages, but the cap in a PF setup sees a much higher signal
>but its "sound" sees no further amplification....????
Hi David....great post. Location of the cap in a para feed output stage can
be located in the ground leg of the ouput transformer. Many builders have
reported a preference for putting the cap in this location....the rationale
being that the cap's sound, as you suggest above, sees no further
amplification.
> I am not personally a big fan of caps anywhere.... any time i have been
>able to avoid one, I have preferred the sound... but moving on in
>thought...
Ironically if your building a conventional SE amplifier topology (meaning your
using a airgapped output) you do have caps in the signal path (thanks to Scott
Nixon for pointing this out to me a long time ago)....the ground path sees all
of the power supply (including caps, chokes, and high voltage secondary
winding) the impedance of this path will be much greater than the impedance of
the para feed's audio ground path.
Seems to me you must always be willing to "hear out" an idea without allowing
archetype prejuidices or notions being able to kill the idea before actually
doing it. I would agree on an abstract level very much with your sense of
KISS...so initially I too would have a bugaboo about "complicating" a circuit
and it's directness or simplicity in just getting the job done. But as I also
suggest above what might appear on first blush to be contrary to this KISS
principle actaully embraces it once we realize all the implications (i.e.,
although para feed puts a cap in the signal path it is small compared to the
cap that is in the signal path when we build a conventional SE amplifier). And
we gain a huge number of other performance advantages in being able to
optimize the output trans and being able to use a wider range of materials in
the optimum configuration.
Also we should be willing to look always at the whole package of benefits vs.
liabilities. Take an ifor instance. If a para feed interstage could offer
much greater AC magnetic headroom, greater primary L in a smaller package
(this helps HF response all other things being equal), and much, much lower
levels of magnetic core distortion then this may be an approach that should be
evaluated with an "open ear" before final judgement is passed. Though again
my prejuidice here would be not to ever use an interstage when direct coupling
btwn the stages in possible. I guess my sense is to use as few of
transformers of the highest quality possible in executing a design.
>I guess there are those that can argue that like transformers, it is much
>easier to build a cap to handle smaller signals (ie change the sound less)
>at which point it becomes that dreaded lesser of two evils... next, all
>theory goes out the window and your ears rule the roost.
Well put Dave. Again....great post on your part. Hopefully other folks will
chime in with their experiences.
=========================================================================
From: Peter Sikking <peter.sikking@amc.de>
Subject: Re: calling all parallel feeders
Date: Wed, 10 Dec 1997 16:02:05 +0100
Source: Sound Digest Archive v01.n130
AirGapped wrote:
> Location of the cap in a para feed output stage can
> be located in the ground leg of the ouput transformer. Many builders have
> reported a preference for putting the cap in this location....the rationale
> being that the cap's sound, as you suggest above, sees no further
> amplification.
Just a question: If you put the cap in the ground leg, and turn your amp
on,
the cap is going to charge up. This means DC through a OPT that is not
designed
to handle it or through the speaker in an OTL case (I have both options
in
my 1962 Philips amp). Is this not a problem?
--Peter
music lover, ultra-fi builder, GUI designer & developer, on drums...
from:amsterdam@ulm.germany +49 731 505 1679 facsimile +49 731 505 1808
=========================================================================
From: AirGapped <AirGapped@aol.com>
Subject: Re: calling all parallel feeders
Date: Wed, 10 Dec 1997 16:49:15 EST
Source: Sound Digest Archive v01.n131
In a message dated 97-12-10 12:14:21 EST, you write:
<<
Just a question: If you put the cap in the ground leg, and turn your amp
on,
the cap is going to charge up. This means DC through a OPT that is not
designed
to handle it or through the speaker in an OTL case (I have both options
in
my 1962 Philips amp). Is this not a problem?
>>
From a practical point of view....this is not anything to worry about. First
bear in mind that this cap is way downstream and typically of relatively small
value (not hundreds of mfd's). What with a decent power supply filtering
section in front of it and a pretty darn big (in most cases) inductor sitting
on top of the plate...no mad rushes of currents are likely to impose
themselves on the output trans.
So at worse it would be a transitory condition of very finite time....and the
absolute magnitude of the current inrush this far down is likely to small.
And remember that you can always put the cap in the upper leg of the
trans...this is how I have it done on my line level preamp.
From a sonic point of view placement of the cap in the upper leg (closest to
the plate of the tube) or the lower leg (nearest ground) produces different
results...but...to my ears...at the preamp level...the differences were not
pronounced and if anything I had (or thought I had) a preference for the cap
in the upper leg and that is where it has stayed.
Mike
=========================================================================
From: JIM_FLOWERS@HP-USA-om24.om.hp.com
Subject: Re: calling all parallel feeders
Date: Wed, 10 Dec 1997 18:39:01 -0500
Source: Sound Digest Archive v01.n131
<<
Just a question: If you put the cap in the ground leg, and turn your
amp on,
the cap is going to charge up. This means DC through a OPT that is not
designed
to handle it or through the speaker in an OTL case (I have both
options in
my 1962 Philips amp). Is this not a problem?
>>
I've never noticed the initial charging current during power-up to be
a problem in my OTL or the parafeed output stage. But then again, I
use a soft-start circuit and/or variac for power-up.
<<
...the differences were not pronounced and if anything I had (or
thought I had) a preference for the cap in the upper leg and that is
where it has stayed.
>>
I use the coupling cap in the upper leg, but not just for sonic
reasons. With the cap in the lower leg, the output tranny insulation
must be able to withstand the voltage gradient between plate voltage
and ground (I don't allow my speaker taps to float). My 845 parafeed
circuit has a plate voltage above 1kV and I'm not convinced the
push-pull OTs I have were designed to work at such an elevated
voltage.
JF
jim_flowers@hp.com
=========================================================================
From: John Levreault <jlevro@shore.net>
Subject: Re: calling all parallel feeders
Date: Wed, 10 Dec 1997 19:18:22 -0500
Source: Sound Digest Archive v01.n131
At 04:02 PM 12/10/97 +0100, Peter Sikking wrote:
>
>Just a question: If you put the cap in the ground leg, and turn your amp
>on,
>the cap is going to charge up. This means DC through a OPT that is not
>designed
>to handle it or through the speaker in an OTL case (I have both options
>in
>my 1962 Philips amp). Is this not a problem?
>
>
DC voltage on the winding is not the problem; DC current flowing through
that winding is.
JL
=========================================================================
From: "Sellek, Grant (DOT)" <Grant.Sellek@roads.sa.gov.au>
Subject: RE: calling all parallel feeders
Date: Thu, 11 Dec 1997 12:52:37 +1030
Source: Sound Digest Archive v01.n131
>From: AirGapped[SMTP:AirGapped@aol.com]
>Ironically if your building a conventional SE amplifier topology (meaning
>your
>using a airgapped output) you do have caps in the signal path (thanks to
>Scott
>Nixon for pointing this out to me a long time ago)....the ground path sees
>all
>of the power supply (including caps, chokes, and high voltage secondary
>winding) the impedance of this path will be much greater than the impedance
>of
>the para feed's audio ground path.
I need a little more help to grasp this. I understand the basic
statement about path 1 (via PS) and path 2 (via OPT). But what does the
relative impedance ratio of the two paths tell us about their respective
contribution to sound quality?
Doesn't adding the parafeed cap to path 2 raise its impedance closer to
that of path 1?
Is it best if the impedance of the two paths are similar, or vastly
different? The more different the better?
From the loudspeaker's point of view, it seems that the parafeed cap is
in series with the signal, and the power supply caps are in parallel.
Are a cap's personal characteristics more obvious when it is in series
than in parallel with the direct signal path?
>.....I also
>suggest above what might appear on first blush to be contrary to this KISS
>principle actaully embraces it once we realize all the implications (i.e.,
>although para feed puts a cap in the signal path it is small compared to the
>cap that is in the signal path when we build a conventional SE amplifier).
So the caps in the pi filter should be of the absolute highest possible
quality?
And smaller values helps in this regard, because small caps generally
have less sonic signature?
Am I concluding that there's a case for CLCLC filters with (purely for
example) 8uf caps instead of the classic CLC with (100+100)uf caps?
Grant
Grant Sellek
Adelaide, Australia
grant.sellek@roads.sa.gov.au
=========================================================================
From: Grego Sanguinetti <grego@latticesemi.com>
Subject: Re: calling all parallel feeders
Date: Thu, 11 Dec 1997 10:54:18 -0800 (PST)
Source: Sound Digest Archive v01.n132
> ......
> So for sonic reasons I prefer to use the "plastics"....but this precludes high
> voltage apps. Remember not only must the insulation package protect against
> DC voltages but in the case of 845's we also have high AC voltages due to the
> high primary impedances typically employed. It gets to be a bear....and full
> of sonically challenging compromises....
>
> You can be sure that when I do an 845\211 output it will be done with the
> requirement that the user put the cap in the upper leg...it's good engineering
> practice in this case plus it will allow us to use some of our favorite
> insulations.
>
> So thanks Jim for the contribution...it made me get over the conceptual hump
> I've had even about doing a para feed 845....
So don't use such high voltages. The 845 sounds very good at lower voltage,
as long as you can feed it current. It is a very flexible tube as far as operating
points are concerned. The PF amp I have now runs either a VV52 or an 845. Not at
the same operating points though, but no higher than 600v.
I interchange them whenever the mood grabs me.
- -grego
"A vibration is a motion that cannot make up its mind which way it wants to go."
=========================================================================
From: AirGapped <AirGapped@aol.com>
Subject: Re: calling all parallel feeders
Date: Thu, 11 Dec 1997 11:57:50 EST
Source: Sound Digest Archive v01.n132
In a message dated 97-12-11 11:00:41 EST, Jim Flowers wrote:
<<
I use the coupling cap in the upper leg, but not just for sonic
reasons. With the cap in the lower leg, the output tranny insulation
must be able to withstand the voltage gradient between plate voltage
and ground (I don't allow my speaker taps to float). My 845 parafeed
circuit has a plate voltage above 1kV and I'm not convinced the
push-pull OTs I have were designed to work at such an elevated
voltage.
>>
Several notes here. But first by way of introduction....Mr. Flowers is the
man who wrote several great articles on transformer theory and basics that
Valve published.
Nice to see you on Joe-list. Interesting that you preferred the cap in the
upper leg of the output trans. I too preferred it in this spot on my preamp
output. Many other notables have preferred the cap in the ground leg for
sonic reasons.
Bill Petrowsky (one of my mentors) always recommended to me that the cap be
put in the upper leg for the voltage reasons you mention above. In most
applications where the plate volts are say less than 500 or 600 volts putting
the cap in the lower leg does not overly stress the insulations (assuming good
engineering practice in the trans design)....
but when you get up to 845 territory...the range of 900 plus volts....the
voltage gradients become wicked...and the opportunities in terms of dielectric
materials selections become attenuated....due to the problem of corona
resistance as well.
I have always shied away from the high voltage tranneys because I was not
happy with the engineering choices that I had realistically. If you design
for high volts (say 1250 plate volts) then your choice of insulations is
severly reduced....any and all of the plastics (teflon, polypropylene,
polystyrene, even mylar) do not have good corona resistance. The materials
with decent corona resistance are mica, kraft paper, glassine, and cotton.
But the problem with these materials are that you must really use them at
around 50 volts per mil (.001" of thickness of material)....so then the
penalty becomes that you wind up using forty to sixty thousandths of
insulations btwn windings for adequate long term voltage protection and your
leakage begins to go through the roof....and this assumes that you like the
sound of mica better than any of the plastics listed above.
So for sonic reasons I prefer to use the "plastics"....but this precludes high
voltage apps. Remember not only must the insulation package protect against
DC voltages but in the case of 845's we also have high AC voltages due to the
high primary impedances typically employed. It gets to be a bear....and full
of sonically challenging compromises....
You can be sure that when I do an 845\211 output it will be done with the
requirement that the user put the cap in the upper leg...it's good engineering
practice in this case plus it will allow us to use some of our favorite
insulations.
So thanks Jim for the contribution...it made me get over the conceptual hump
I've had even about doing a para feed 845....
Mike
=========================================================================
From: Bart Shepherd <bartonw@ozemail.com.au>
Subject: Calling Altec Experts / Horn Lovers - Help needed (long)
Date: Thu, 23 Jul 1998 21:37:45 +1000
Source: Sound Digest Archive v01.n354
Hi Fellow Joesters,
I have the opportunity to buy some Altec gear.
Was supposedly A7's but some theatre sound expert put the F416-8's in about 5
cu ft boxes with a bout a 4 inch x 1.5 inch long port!
Heard them demoed with an SS amp and CD. Too close and too far apart.
Rest of speaker setup was 902-8 HF drivers with 511B horns and N501-8 xover
with level knob.
Sound was very disappointing, little dynamics compared to the reputation that
set my expectations (never knowingly heard Altecs before i.e. outside
theatres). Extreme top seemed missing, mids pretty good, bass very boomy and
one noteish, no real very low bass (<45hz). Imaging - I couldn't tell due to
poor setup. No nastiness. 511B's look disappointingly cheaply made with
obvious joints between top and bottom halves (worry about Alters claim to
quality) and ring like bells!!
If I left it at that I would dismiss all this Alter stuff and all the hype
about A "n"'s as crap!
But I have confidence in you Altec lovers and believe something must be amiss -
bass enclosure seems very suspect.
My question is: can I make a silk purse out of these parts??
I have read (SP) to go for the 500Hz xover and horns rather than the 800Hz
(e.g. 802 / 811 combination). Is this good advice?
The bottom line is: Can I make a VERY good speaker system from these
components?
I want 100db+. Do I need to add a tweeter? What sort of bass box should I
build? Onken? Karlson? (does anyone have measurements etc for these?)
How much should I pay for these parts?
I can buy 3 511B horns, 3 902-8 drivers, 3 N501-8 xovers (do I want these??)
and 4 F416-8 bass drivers. If I could find some more bits at reasonable prices
I almost could make 2 pairs.
All assistance greatly appreciated. I have to move fast if I am to go ahead.
Please advise as to where I can be successful with this stuff and how much to
pay.
Than-Ks & cheers,
Bart
=========================================================================
From: Bart Shepherd <bartonw@ozemail.com.au>
Subject: RE: Calling Altec Experts / Horn Lovers - Help needed (long)
Date: Fri, 24 Jul 1998 02:11:02 +1000
Source: Sound Digest Archive v01.n355
Hi Tom,
Thanks for the advice.
re dynamics -I guess I meant was transients. i.e. pianists with strong
sounding fingers so you know when they hit a note hard, kick drums with kick in
the guts and real zing when a drummer rides on the bell of a cymbal. The setup
I heard even with plenty SS amp power did none of these things.
Maybe wasn't the raw drivers but sure was the result. I gave it every chance
with normal CD's and a Chesky demo disk plus the mega expensive propius xrcd
"Jazz in a Pawnshop" double.
I hate to say it but the guy getting rid of them was in the theatre / movie
business and had a set of NHT towers.
The argument being put forward on the list and SP for real dynamics / low
distortion is for flea power 45's / 2A3's and 100+ db speaks. It's hard to
find Altecs here in Australia and from what I've heard to date I'd bet on 70
- -100watt amps with 90 - 96 db speakers blowing that approach away!
I realise I'm setting myself up to be either scorned or flamed but I fall back
on the question - how many of them have had a good solid 1000 - 1250 volts to
really try the difference with SET?
I hope I dont go the way of Purl or Jute for daring to vary from the
politically correct party line!
Bart (BTW still may buy the Altec drivers but will need plenty xover, cabinet
design help!)
- ----------
From: tom brennan[SMTP:irishtom@webtv.net]
Sent: Friday, July 24, 1998 12:55 AM
To: sound@deliverator.io.com
Subject: Fwd: Calling Altec Experts / Horn Lovers - Help needed (long)
<<Message: Calling Altec Experts / Horn Lovers ...>>
Bart---Perhaps the poor bass is because the box is poorly designed,
vented boxes are tricky, but a proper, good sounding box for the 416s
can certainly be done. Yon play with crossovers or add a tweeter to
extend the high end, I've used EV T-35s with my Altecs at times. The
thing is though that if you didn't hear magic with the Altecs maybe
they're just not for you. You might spend money and time on these and
still end up with something you don't like. I've always liked Altecs in
stock form, I key in on the strengths (to me) of their sound, then if I
can tweak them better fine. I'm at a loss to understand your perception
of poor dynamics. I wouldn't worry about the unground weld on the
outside of the 511s, grinding and poishing that weld would serve no
functional purpose, in my trade we don't flattop high pressure boiler
and pressure vessel welds so why flattop the outside of a horn? I'm
curious, what speakers do you think do have good dynamics?
Tom Brennan
=========================================================================
From: Douglas Purl <dcp@selway.umt.edu>
Subject: RE: Calling Altec Experts / Horn Lovers - Help needed (long)
Date: Thu, 23 Jul 1998 17:35:35 -0600 (MDT)
Source: Sound Digest Archive v01.n356
On Fri, 24 Jul 1998, Bart Shepherd wrote:
> I hope I dont go the way of Purl or Jute for daring to vary from the
> politically correct party line!
I am amazed to see hornies picking their scabs in public, but it's a
welcome sight.
I think I left by the door. Did Andre the Armbreaker leap or get pushed?
I don't intend to cause a ruckus. I consider tubes heartbreakers, since
they decay steadily, like requited love. And horns are teases, always
promising more than they deliver. I consider them pastimes for those
intoxicated with perpetual foreplay. But I like the theoretical
discussions here, sometimes. Big brains, big knowledge.
Maybe I'll hang around long enough to deflect attention from your
apostasy, Bart. I did see some postings yesterday that made my toes
twitch. Such as this curious belief that less is better in amplifiers.
Not many circuit designers would agree. But I guess every list needs a
religion.
Doug Purl
=========================================================================
From: "Doc B." <bottlehead@silverlink.net>
Subject: Re: Calling Altec Experts / Horn Lovers - Help needed (long)
Date: Thu, 23 Jul 1998 17:39:22 -0700
Source: Sound Digest Archive v01.n356
But I guess every list needs a
>religion.
If for no other reason than giving one chance to declare himself heresiarch,
eh?
Doc B.
=========================================================================
From: Grego Sanguinetti <grego@lscpdx.latticesemi.com>
Subject: Re: Calling Altec Experts / Horn Lovers - Help needed (long)
Date: Thu, 23 Jul 1998 18:09:22 -0700
Source: Sound Digest Archive v01.n356
Bart,
My advice is walk away from the deal.
I grew up with Altecs. I had a system
consisting of VOT's in the 60's. I left them
along time ago to pursue more "conventional"
systems and then EL's, finally pannels and
now I am back to VOT's!
I am one whom can filter the weak to enjoy
the good. I hope that doesn't change for me.
I have a hard time with stock 511 horns. They
really must be modified. Even then they are
still flawed. I have mine to the point where
I am happy and my wife is happy but if she
would let me I would go for the bigger multi
cellular....
I am a bass player, but I love the sound of
bass through the VOT's. I would like to have
a little more in the bottom end. One of these
days I will find away to do that and stay
within my constraints.
The bottom you are listening to is not a
VOT so who knows. You can also create a bad
system with fine components.
Purchasing for tube amps I would choose the
16ohm drivers instead of the 8ohms.
I think in summary that I would not purchase
those components. I would hold out for 16ohm
drivers, in a system that had more promise
to start with.
The bottom of the VOT covers quite a bit
of range and if you didn't hear good dynamics
I suspect that bottom unit.
Wait until you find something that you can
really hear potential in and then you will know
where to start fixing it.... I liked my Altecs
but heard obvious problems with them that I
felt I knew how to fix. That is the position
you want to be in to start.
By the way Doug. I am a circuit designer who
strongly believes that a good solution is
even better if it is simpler. Minimum parts
count is always in the first few optimization
contraints.
- -grego
=========================================================================
From: William Eckle <wmeckle@uswest.net>
Subject: RE: Calling Altec Experts / Horn Lovers - Help needed (long)
Date: Thu, 23 Jul 1998 18:42:16 -0700
Source: Sound Digest Archive v01.n356
At 05:35 PM 7/23/98 -0600, Douglas Purl wrote:
>
>I think I left by the door. Did Andre the Armbreaker leap or get pushed?
Hi Doug:
Pretty much pushed.
-=Bill Eckle=- Note:
Please Change my address From:
wmeckle@primenet.com To:
wmeckle@uswest.net
=========================================================================
From: Bob C <bobc@mci2000.com>
Subject: Re: Calling Altec Experts / Horn Lovers - Help needed (long)
Date: Thu, 23 Jul 1998 23:13:16 -0700
Source: Sound Digest Archive v01.n356
- -----Original Message-----
From: Hugh R. Dean <aspen@alphalink.com.au>
To: sound@deliverator.io.com <sound@deliverator.io.com>
Date: Thursday, July 23, 1998 5:33 PM
Subject: Re: Calling Altec Experts / Horn Lovers - Help needed (long)
>
>Andre, perhaps sadly, was pushed.
Sadly perhaps, for one who enjoys nonstop projectile vomiting!
Bob
=========================================================================
From: "Johari Yip" <hfyip@pacific.net.sg>
Subject: Re: Calling Altec Experts / Horn Lovers - Help needed (long)
Date: Fri, 24 Jul 1998 09:11:34 +0800
Source: Sound Digest Archive v01.n356
- ----------
> From: Bart Shepherd <bartonw@ozemail.com.au>
> To: sound@deliverator.io.com; 'tom brennan' <irishtom@webtv.net>
> Subject: RE: Calling Altec Experts / Horn Lovers - Help needed (long)
> Date: Friday, July 24, 1998 12:11 AM
>
> Hi Tom,
>
> Thanks for the advice.
>
> re dynamics -I guess I meant was transients. i.e. pianists with strong
> sounding fingers so you know when they hit a note hard, kick drums with
kick in
> the guts and real zing when a drummer rides on the bell of a cymbal. The
setup
> I heard even with plenty SS amp power did none of these things.
>
> Maybe wasn't the raw drivers but sure was the result. I gave it every
chance
> with normal CD's and a Chesky demo disk plus the mega expensive propius
xrcd
> "Jazz in a Pawnshop" double.
>
> I hate to say it but the guy getting rid of them was in the theatre /
movie
> business and had a set of NHT towers.
>
> The argument being put forward on the list and SP for real dynamics / low
> distortion is for flea power 45's / 2A3's and 100+ db speaks. It's hard
to
> find Altecs here in Australia and from what I've heard to date I'd bet on
70
> -100watt amps with 90 - 96 db speakers blowing that approach away!
>
> I realise I'm setting myself up to be either scorned or flamed but I fall
back
> on the question - how many of them have had a good solid 1000 - 1250
volts to
> really try the difference with SET?
>
> I hope I dont go the way of Purl or Jute for daring to vary from the
> politically correct party line!
>
> Bart (BTW still may buy the Altec drivers but will need plenty xover,
cabinet
> design help!)
Bart
All I can say is, you have a lot of work to do if you decides to stick with
the Altec purchase. Most of the Altec set-up I've heard are pure labour of
love. Correct me if I'm wrong but I get the impression that you do have
limited exposure to a well sat up multi-way horn based (Altec or otherwise)
system or a hornspeaker with a full range single way driver (Lowther and
the likes). Dynamics is one of the many virtues that music lovers go for
this set up.
Best Regards,
Johari
=========================================================================
From: "Hugh R. Dean" <aspen@alphalink.com.au>
Subject: Re: Calling Altec Experts / Horn Lovers - Help needed (long)
Date: Fri, 24 Jul 1998 10:21:07 +1000
Source: Sound Digest Archive v01.n356
Hi Doug, you wrote:
> I am amazed to see hornies picking their scabs in public, but it's a
> welcome sight.
>
> I think I left by the door. Did Andre the Armbreaker leap or get pushed?
> I don't intend to cause a ruckus. I consider tubes heartbreakers, since
> they decay steadily, like requited love. And horns are teases, always
> promising more than they deliver. I consider them pastimes for those
> intoxicated with perpetual foreplay. But I like the theoretical
> discussions here, sometimes. Big brains, big knowledge.
Ah, a most joyous splash! My screen lit up like a solar prominence.
Welcome back Doug.
I favour the arranged marriage; the small tube, without passion and
fanfare, seems to last the longest. The large, tumescent tubes seem to
flicker and die rather quickly by comparison. Your comment about
requited love betokes a shrewd view of life; perhaps a fullsome youth,
Doug?
Agree about the horns. Feel the same about electrostatics. A
marvellous engineering solution with great potential but a deficient
realisation. Who wants to hear harps in heaven? Not ready yet...
Andre, perhaps sadly, was pushed. Rather controversial and acrimonious.
Cheers,
Hugh
- --
-== Hugh R. Dean ==-
aspen@alphalink.com.au
Melbourne, Victoria, AUSTRALIA
=========================================================================
From: Douglas Purl <dcp@selway.umt.edu>
Subject: Re: Calling Altec Experts / Horn Lovers - Help needed (long)
Date: Thu, 23 Jul 1998 23:42:58 -0600 (MDT)
Source: Sound Digest Archive v01.n357
On Thu, 23 Jul 1998, Doc B. wrote:
> But I guess every list needs a
> >religion.
>
>
> If for no other reason than giving one chance to declare himself heresiarch,
> eh?
Right on, bro, er, Doc.
Doug Purl
=========================================================================
From: Douglas Purl <dcp@selway.umt.edu>
Subject: Re: Calling Altec Experts / Horn Lovers - Help needed (long)
Date: Fri, 24 Jul 1998 00:08:02 -0600 (MDT)
Source: Sound Digest Archive v01.n357
On Thu, 23 Jul 1998, Grego Sanguinetti wrote:
> By the way Doug. I am a circuit designer who
> strongly believes that a good solution is
> even better if it is simpler. Minimum parts
> count is always in the first few optimization
> contraints.
Perhaps my message suffered from a want of components in the sentence. I
was suggesting that minimilization is neither the sufficient nor necessary
condition of superior performance. Moreover, in audio amplifiers,
simplification can result in performance compromises. Of course good
designers make saavy compromises. But they are compromises.
See, Bart? I am your virtual human shield.
Doug Purl
=========================================================================
From: Grego Sanguinetti <grego@lscpdx.latticesemi.com>
Subject: Re: Calling Altec Experts / Horn Lovers - Help needed (long)
Date: Fri, 24 Jul 1998 11:46:47 -0700
Source: Sound Digest Archive v01.n358
On Fri, Jul 24, 1998 at 12:08:02AM -0600, Douglas Purl wrote:
.....
> Perhaps my message suffered from a want of components in the sentence. I
> was suggesting that minimilization is neither the sufficient nor necessary
> condition of superior performance.
Absolutely agreed.
> Moreover, in audio amplifiers,
> simplification can result in performance compromises. Of course good
> designers make saavy compromises. But they are compromises.
Not sure there is any real point there. All we listen to are compromises.
The goodness of the product is the balance of the compromises, right?
Perhaps there are not enough components connected between my ears/eyes?
> See, Bart? I am your virtual human shield.
Yeah but damn, Doug's back on the list and now I have to dig out
the dictionary and keep it next to the computer. Not just any
dictionary. I had to get the good one to find heresiarch! Great word!
just don't expect me to up my writting style trying to sound like
Doug. I is what I is and that's all there is too it, a hick.
By the way, welcome back Doug, you crack me up B^)
- -grego, burp.
- -------
oh, sh*t, first these pukes talk about "submicron" technology,
then they found "deep submicron".
Now some guy is talking to me about "nanometer" technology.
Geesh, did all these CAD vendor marketing pukes come from the
Bob Carver school of marketing hype?!! and each time they
come up with a new buzzword, they try to sell me the same
tool, but add on an extra $20,000 or so because it now supports
their made up buzzword!!!
oh, don't let me get started.....
=========================================================================
From: Douglas Purl <dcp@selway.umt.edu>
Subject: Re: Calling Altec Experts / Horn Lovers - Help needed (long)
Date: Fri, 24 Jul 1998 14:56:35 -0600 (MDT)
Source: Sound Digest Archive v01.n358
On Fri, 24 Jul 1998, Grego Sanguinetti wrote:
> Yeah but damn, Doug's back on the list and now I have to dig out
> the dictionary and keep it next to the computer. Not just any
> dictionary. I had to get the good one to find heresiarch! Great word!
Hey, give the old devil his due. That was Doc Brains, alias Bottlehead.
All his words are gaseous.
Doug Purl
=========================================================================
From: Grego Sanguinetti <grego@lscpdx.latticesemi.com>
Subject: Re: Calling Altec Experts / Horn Lovers - Help needed (long)
Date: Fri, 24 Jul 1998 16:14:51 -0700
Source: Sound Digest Archive v01.n358
> Aw, come on. That was an elementary school word. My old ISP logon was
> Hexagesic. Look that one up!;->
A*sh*le! Ok you overflowed very dictionary on my isle.
spill the beans d*ck head!
Damn, now I need a 4th edition AND and 50lb dictionary...
I'm too old for this...sorry Bill, I mean young B^)
And while I am at it, swear on an oath that you didn't
have to look up heresiarch!
HEY gang, I may not have your vocabulary but I just got back
from lunch, at the Portland Brewers Festival. On the waterfront,
some 70+ micro breweries and a bunch of local resturants.
Beautiful day, just the right temperature, hot but not too hot,
just the right breeze off the water... Jelly?
- -grego
- -------------------------------------------------------------
I measure bad times by how many people in the world I think
would want to trade places with me. I think I am up a billion
today B^)
=========================================================================
From: Scott Grammer <tubedude@cdc.net>
Subject: Re: Calling Altec Experts / Horn Lovers - Help needed (long)
Date: Fri, 24 Jul 1998 17:10:39 -0400
Source: Sound Digest Archive v01.n358
Douglas Purl wrote:
> On Fri, 24 Jul 1998, Grego Sanguinetti wrote:
>
> > Yeah but damn, Doug's back on the list and now I have to dig out
> > the dictionary and keep it next to the computer. Not just any
> > dictionary. I had to get the good one to find heresiarch! Great word!
>
> Hey, give the old devil his due. That was Doc Brains, alias Bottlehead.
> All his words are gaseous.
>
> Doug Purl
Aw, come on. That was an elementary school word. My old ISP logon was
Hexagesic. Look that one up!;->
S.G.
- --
Check out TubeDude's Webpage of vacuum Tube Lore!
http://www.cdc.net/~tubedude/
=========================================================================
From: Grover Gardner <groverg@postoffice.att.net>
Subject: Re: Calling Altec Experts / Horn Lovers - Help needed (long)
Date: Fri, 24 Jul 1998 20:01:51 -0500
Source: Sound Digest Archive v01.n358
At 5:10 PM -0400 7/24/98, Scott Grammer wrote:
>Douglas Purl wrote:
>
>> On Fri, 24 Jul 1998, Grego Sanguinetti wrote:
>>
>> > Yeah but damn, Doug's back on the list and now I have to dig out
>> > the dictionary and keep it next to the computer. Not just any
>> > dictionary. I had to get the good one to find heresiarch! Great word!
>>
>> Hey, give the old devil his due. That was Doc Brains, alias Bottlehead.
>> All his words are gaseous.
>>
>> Doug Purl
>
>Aw, come on. That was an elementary school word. My old ISP logon was
>Hexagesic. Look that one up!;->
As Somerset Maugham once said, the good writer will always choose the
shorter word, and let the longer one fall into desuetude.
Grover Gardner
groverg@postoffice.att.net
=========================================================================
From: Scott Grammer <tubedude@cdc.net>
Subject: Re: Calling Altec Experts / Horn Lovers - Help needed (long)
Date: Fri, 24 Jul 1998 20:46:33 -0400
Source: Sound Digest Archive v01.n358
Grego Sanguinetti wrote:
> (snip)
> A*sh*le! Ok you overflowed very dictionary on my isle.
> spill the beans d*ck head!
>
> (snip)
> And while I am at it, swear on an oath that you didn't
> have to look up heresiarch!
> (snip)
OK, I admit it. I cheated. Hexagesic is a bastardization of sexagesimal,
which is the name for base 60 mathmatics. As in clocks. And yes, I did have
to look up heresiarch!I didn't thing that "Sexagesic" would lend the
intended meaning if I used it as a screen name.......
Cheers!
S.G.
- --
Check out TubeDude's Webpage of vacuum Tube Lore!
http://www.cdc.net/~tubedude/
=========================================================================
From: "Doc B." <bottlehead@silverlink.net>
Subject: Re: Calling Altec Experts / Horn Lovers - Help needed (long)
Date: Fri, 24 Jul 1998 20:49:36 -0700
Source: Sound Digest Archive v01.n359
>HEY gang, I may not have your vocabulary but I just got back
>from lunch, at the Portland Brewers Festival. On the waterfront,
>some 70+ micro breweries and a bunch of local resturants.
>Beautiful day, just the right temperature, hot but not too hot,
>just the right breeze off the water... Jelly?
>
>-grego
>-------------------------------------------------------------
>I measure bad times by how many people in the world I think
>would want to trade places with me. I think I am up a billion
>today B^)
>
>
Sorry holmes, while you sent this I was sea kayaking on Liberty Bay with
Queen Eileen, followed by a dinner of potstickers, cashew chicken and ginger
beef and a tour of a display of Poulsbo boats (very cool, planked hull open
boats about 16' long, from the 30's and 40's, with Briggs and Stratton
inboard one lungers sitting right out in the middle of the boat), while
grandma watched the kids. Don't wanna trade.
Doc B.
=========================================================================
From: "Ken Dangerfield" <bpyakd@mail.island.net>
Subject: Camille Power Supply
Date: Thu, 15 Oct 1998 16:22:43 -0800
Source: Sound Digest Archive v01.n456
I'm going to have to pay more attention to the address fields in my
replies. I meant to reply personally to Hopper and not to the entire
list with my offer to fax a copy of Buddha's design. I'll go broke
faxing copies to the entire list scattered around the world!!
Here's what I'm going to do. I will get the original copy
from Buddha (I only have a fax copy) and his permission to distribute
it, and then arrange for it to be scanned and put on a site where
everyone can access it (Doc's or Scott's come to mind).
Alternatively, Jim Flowers or one of you other guys in Texas who has
access to a good scanner could do the same thing because Buddha lives
right there in your back yard. I say a good scanner because
sometimes Buddha's hand writing can be very small and difficult to
read.
BTW, keep in mind that this is not necessarily Buddha's optimum
design or piece de resistance. He designed this ps specifically to
be an after the fact upgrade to the John Tucker designed 2A3
Afterglow amps, with a minimum of outlay for parts and using the
stock power xfrmr supplied with the kit from Doc B. (Although it
does call for a separate power xfrmr and supply for the filaments).
Jim or someone else in Texas let me know if you can handle the
scanning down there instead of waiting for the snail mail from
Buddha to reach me up here in the far reaches of the rain forest.
Unfortunately, Buddha doesn't use computers/email (except the very
impressive one in his cranium).
Regards,
Ken Dangerfield
=========================================================================
From: Paul Joppa <pdj@ISDNseattle.net>
Subject: Re: Camille Power Supply
Date: Fri, 16 Oct 1998 10:12:20 -0700
Source: Sound Digest Archive v01.n456
Ken Dangerfield wrote:
> ...snip... the John Tucker designed 2A3
> Afterglow amps, ...snip...
To be fair, I believe that amp was designed by John and Doc
*together*.
- -Paul Joppa
=========================================================================
From: "Doc B." <bottlehead@silverlink.net>
Subject: Re: Camille Power Supply
Date: Fri, 16 Oct 1998 11:48:28 -0700
Source: Sound Digest Archive v01.n456
Thanks Paul.
Doc B.
www.bottlehead.com
- -----Original Message-----
From: Paul Joppa <pdj@ISDNseattle.net>
To: Ken Dangerfield <bpyakd@mail.island.net>
Cc: sound@deliverator.io.com <sound@deliverator.io.com>
Date: Friday, October 16, 1998 11:09 AM
Subject: Re: Camille Power Supply
>Ken Dangerfield wrote:
>> ...snip... the John Tucker designed 2A3
>> Afterglow amps, ...snip...
>
>To be fair, I believe that amp was designed by John and Doc
>*together*.
>
>-Paul Joppa
>
=========================================================================
From: Grover Gardner <groverg@postoffice.att.net>
Subject: Re: Camille Power Supply
Date: Fri, 16 Oct 1998 12:41:28 -0500
Source: Sound Digest Archive v01.n456
At 4:22 PM -0800 10/15/98, Ken Dangerfield wrote:
>I'm going to have to pay more attention to the address fields in my
>replies. I meant to reply personally to Hopper and not to the entire
>list with my offer to fax a copy of Buddha's design. I'll go broke
>faxing copies to the entire list scattered around the world!!
>
>Here's what I'm going to do. I will get the original copy
>from Buddha (I only have a fax copy) and his permission to distribute
>it, and then arrange for it to be scanned and put on a site where
>everyone can access it (Doc's or Scott's come to mind).
Ken, I already have Camille's VSAC stuff in .gif or .jpeg format--Tom Ronan
sent them to me some time ago. I can e-mail them to whoever wants to put
them on a web site if you like.
Grover Gardner
groverg@postoffice.att.net
=========================================================================
From: "Ken Dangerfield" <bpyakd@mail.island.net>
Subject: Camille Power Supply
Date: Mon, 2 Nov 1998 08:05:22 -0800
Source: Sound Digest Archive v01.n477
To everyone who requested a copy of the schematic for John Camille's
power supply for the 2A3 Afterglows (and there were lots of you). I
haven't faxed it out because of (a) cost of faxing to so many people
in so many far flung places and (b) I'm not sure it would be very
legible because I only have a fax copy myself.
But I have spoken to John and he doesn't have any problem with his
design being made available to members of the list (with the usual
disclaimers about YMMV). He's going to mail the original hard copy
to Doc B. to be posted on Doc's site. Doc or I will inform the list
when its up there.
Regards,
Ken Dangerfield
=========================================================================
From: Dave Stagner <dstagner@icarus.net>
Subject: Re: Camille Power Supply
Date: Tue, 3 Nov 1998 21:07:17 -0600 (EST)
Source: Sound Digest Archive v01.n479
On Mon, 2 Nov 1998, Ken Dangerfield wrote:
> But I have spoken to John and he doesn't have any problem with his
> design being made available to members of the list (with the usual
> disclaimers about YMMV). He's going to mail the original hard copy
> to Doc B. to be posted on Doc's site. Doc or I will inform the list
> when its up there.
Some copies of the schematic (Grover Gardner's scans of the fax) are
already up at http://www.bottlehead.com/valve/camilleps.shtml
If the good Doctor would be so kind as to send me the originals or clean
photocopies, i'll work on getting cleaner scans.
- -dave
Practice beautiful randomness and act kind of senseless.
<dstagner@icarus.net>
=========================================================================
From: Patrick Currie <tubesguy@mail.chorus.net>
Subject: Re: Camille Power Supply
Date: Thu, 5 Nov 1998 08:09:59 -0600
Source: Sound Digest Archive v01.n481
>Some copies of the schematic (Grover Gardner's scans of the fax) are
>already up at http://www.bottlehead.com/valve/camilleps.shtml
>
>If the good Doctor would be so kind as to send me the originals or clean
>photocopies, i'll work on getting cleaner scans.
>
>-dave
Thanks Dave and Grover for posting what is on the site now. That is what I
did to my amp after returning from this year's VSAC. Made the old (damper
diode) supply sound a little slow and a little dirty by comparison.
I'm really looking forward, however, to the "high-tech shunt regulated"
portion of the new design. Please let us know when it is posted. - Pat
=========================================================================
From: "Nilson, Bruce" <NilsonBruce@FCB.COM>
Subject: Camille power supply schematic
Date: Wed, 19 Nov 1997 10:15:00 -0500
Source: Sound Digest Archive v01.n114
For those interested in obtaining a schematic of John Camille's great
power
supply design (he approves of this), e-mail me your address and I'll
snail
mail it to you, in the US only. Overseas, send $3.
Bruce Nilson
=========================================================================
From: "Sellek, Grant (TSA)" <Grant.Sellek@roads.sa.gov.au>
Subject: Camille PS discussion
Date: Thu, 05 Nov 1998 10:15:16 +1030
Source: Sound Digest Archive v01.n481
Having just looked through the Camille PS VSAC
notes Dave put on the Bottlehead site, I find
them awe-inspiring, not to mention mortifying.
I would love to see some discussion on his
suggestions, and I would be in absolute learner
mode if I contributed. I could think of a handful
of questions in short order.
But first, a precursory question. There is a lot
of work in implementing the system to get hum well
down (John makes it clear that hum is the big demon),
but wouldn't it all be for nought if one used a DHT
output valve with AC filaments? So are all-DC
filaments a prerequisite for this system? What do
the members of the DHT/AC fan club do, just put up
with 9-bit performance at best?
Which raises the pre-precursory question (now you're
getting to see the convoluted way my mind works).
How important is better-than-average (9-bit is average,
14 to 16-bit is excellent) noise performance? Some
people say "If I don't notice noise/hum in quiet
passages of music, there is no problem". Is this
attitude sufficient for great sound, or are "better-
- -than-inaudible" improvements in noise performance
yielding continuous improvements in musical texture,
tonality, etc?
Grant Sellek
Adelaide, Australia
grant.sellek@roads.sa.gov.au
=========================================================================
From: Grover Gardner <groverg@postoffice.att.net>
Subject: Camille PS pix
Date: Sat, 17 Oct 1998 09:58:12 -0500
Source: Sound Digest Archive v01.n457
Folks, I've sent the Camille VSAC scans to Dave Stagner, who will put them
on the Bottlehead site if there are no problems.
Grover Gardner
groverg@postoffice.att.net
=========================================================================
From: An-shyang Chu <achu@sandia.gov>
Subject: Camille PS tricks ?
Date: 15 Oct 1998 08:38:57 -0600
Source: Sound Digest Archive v01.n455
Hey Pat!
Keep hearing this Camille PS tricks, but never find a full description of it.
Can you fill me in on this? What kind of common mode choke have you tried?
Best regards,
hopper
_______________________________________________________________________________
...
Have you tried the Camille PS tricks? A little filter after the diodes
with .01 caps and 10 ohm resistors, then a common mode choke downstream
before the input choke? Could be your answer. - Pat (PS - Pack to
rebound, win by 17)
Pat Currie (tubesguy@execpc.com)
=========================================================================
From: "Ken Dangerfield" <bpyakd@mail.island.net>
Subject: Re: Camille PS tricks ?
Date: Thu, 15 Oct 1998 14:02:43 -0800
Source: Sound Digest Archive v01.n456
On 15 Oct 98 An-shyang Chu said:
> Keep hearing this Camille PS tricks, but never find a full
> description of it. Can you fill me in on this? What kind of common
> mode choke have you tried?
I have a schematic for a Camille designed ps for my 2A3 Afterglow
amps, which includes a separate supply for the filament and a delayed
on and off relay setup. If you're interested, I can fax it to you.
It will probably give you an idea of "Buddha's" approach to ps
filtering using common mode chokes.
Regards,
Ken Dangerfield
=========================================================================
From: "Frank Deutschmann" <fdeutsch@bfm.com>
Subject: Cancer
Date: Sun, 26 Oct 1997 16:17:22 -0500
Source: Sound Digest Archive v01.n089
I have just now, for the benefit of those who may have forgotten, taken the
liberty of re-posting to the list some of Jute's earlier posts; I urge you
all to read them again, and realize just how awful this cancer which has
invaded our world is.
These posts were written by Jute as his "Grand Re-Entrance" to JoeNet, after
an alleged absence of only a few weeks; these posts were written without
provocation by anyone on the list. Instead, Jute re-joined this forum in a
hail of false accusations and insults. He has never apologized for this
behavior. And now, he has the gall to claim himself as victim.
I would like to reiterate what Ron said: your private support is much
appreciated, but if you really value JoeNet, your public support would go a
long way to achieving what you have told me you want: a Jute-free JoeNet.
- -frank
=========================================================================
From: Bob Chernofsky <bobc@mci2000.com>
Subject: Re: Cancer
Date: Sun, 26 Oct 1997 20:27:58 -0800
Source: Sound Digest Archive v01.n089
- -----Original Message-----
From: Frank Deutschmann <fdeutsch@bfm.com>
To: sound@lists.io.com <sound@lists.io.com>
Date: Sunday, October 26, 1997 2:08 PM
Subject: Cancer
>snip<
>I would like to reiterate what Ron said: your private support is much
>appreciated, but if you really value JoeNet, your public support would go a
>long way to achieving what you have told me you want: a Jute-free JoeNet.
>
>-frank
I agree, this is a very special place but it currently has a disease.
Diseases can really fool you. Please don't be fooled.
One way they fool you,is that when they are on the ropes, they try to mix
back in.
Try to identify with you. Try to reattach with you.
(You can still see the diseased cells mixed in no matter how harmless they
try to act.)
Please take a look at a recent post by AJ.
(Subject: Re: Direct (or any) coupling, WAS 300B Amp from Costruire HIFI)
Does not seem bad at all. (Please don't be FOOLED!)
I am not doctor, but I play one on the JoeNet...
Bob
=========================================================================
From: Andre Jute <andre@indigo.ie>
Subject: Re: Cancer
Date: Mon, 27 Oct 1997 02:08:49 GMT
Source: Sound Digest Archive v01.n089
This is a despicable attempt to sweep up people in your net of spite, Frank.
I suppose it was too much for your petty little soul that since then I had
amicable public converse with some of the people involved in that flame war
and was privately making progress with others. You would just hate anyone
openminded enough to carry no grudges; so now you scratch open old wounds
and try to set the dogs on each other again. I feel deeply sorry for you.
I have better things to do than refight old flame wars.
Andre
At 4:17 pm -0500 26/10/97, Frank Deutschmann wrote:
>I have just now, for the benefit of those who may have forgotten, taken the
>liberty of re-posting to the list some of Jute's earlier posts; I urge you
>all to read them again, and realize just how awful this cancer which has
>invaded our world is.
>
>These posts were written by Jute as his "Grand Re-Entrance" to JoeNet, after
>an alleged absence of only a few weeks; these posts were written without
>provocation by anyone on the list. Instead, Jute re-joined this forum in a
>hail of false accusations and insults. He has never apologized for this
>behavior. And now, he has the gall to claim himself as victim.
>
>I would like to reiterate what Ron said: your private support is much
>appreciated, but if you really value JoeNet, your public support would go a
>long way to achieving what you have told me you want: a Jute-free JoeNet.
>
>-frank
Andre Jute
andre@indigo.ie
COMMUNICATION JUTE
- --we support pages for music lovers, writers and audiophiles at
http://www.foundmark.com/ComJute/ComJuteF1.html
=========================================================================
From: Bob Chernofsky <bobc@mci2000.com>
Subject: re; Cancer
Date: Mon, 27 Oct 1997 01:59:23 -0800
Source: Sound Digest Archive v01.n090
- -----Original Message-----
From: Frank Deutschmann <fdeutsch@bfm.com>
To: sound@lists.io.com <sound@lists.io.com>
Date: Sunday, October 26, 1997 2:08 PM
Subject: Cancer
>snip<
>I would like to reiterate what Ron said: your private support is much
>appreciated, but if you really value JoeNet, your public support would go a
>long way to achieving what you have told me you want: a Jute-free JoeNet.
>
>-frank
I agree, this is a very special place but it currently has a disease.
Diseases can really fool you. Please don't be fooled.
One way they fool you,is that when they are on the ropes, they try to mix
back in.
Try to identify with you. Try to reattach with you.
(You can still see the diseased cells mixed in no matter how harmless they
try to act.)
Please take a look at a recent post by AJ.
(Subject: Re: Direct (or any) coupling, WAS 300B Amp from Costruire HIFI)
Does not seem bad at all. (Please don't be FOOLED!)
I am not doctor, but I play one on the JoeNet...
Bob
=========================================================================
From: Ron Bales <rbales@mail.gte.net>
Subject: Re: Cancer
Date: Mon, 27 Oct 1997 19:32:52 -0500
Source: Sound Digest Archive v01.n091
Andre Jute is NOT subscribed to the list. Do not address mail to him on
the list, it will not get to him. It will only be read by your fellow
list members. Your fellow list members are fine people and should not
be subjected to any more dis-harmony than is necessary.
This was a terrorist attack. Jute has noted that many people are upset
by the flames, thus he has posted antagonizing libels to the list hoping
for equally hostile replies which he will not read. The hope is that he
will turn more people against those whom he has declared his enemies.
Apparently Jute IS happy in a country where decent people can hardly own
a fowling piece and the terrorists have mortars.
Ron
Andre Jute wrote:
>
> Yo Gary
>
> Comparing Frank Deutschmann to Adolf Hitler is unfair to Hitler, who,
> absent the demonology of propaganda, was cultured and intelligent whereas
> Deutschmann is merely civilized (it means nothing more than that he lives
> in a city, like any peasant dispossessed of land) and superficially clever
> in the style of so many with only a technical education. I see Deutchmann
> rather as the Maximum Lider, El Grandioso Cigar-O-Gem, a stagey but
> ultimately empty cloak, than real evil.
=========================================================================
From: goyo <goyo@scils.rutgers.edu>
Subject: RE: Cancer
Date: Mon, 27 Oct 1997 21:35:45 -0500
Source: Sound Digest Archive v01.n091
Andre Jute wrote:
>Yo Gary
>
>Comparing Frank Deutschmann to Adolf Hitler is unfair to Hitler, who,
>absent the demonology of propaganda, was cultured and intelligent
I think we should be careful with these kinds of differentiations. This
type of categorizing of Hitler ignores the fact that that the culture and
intelligence he had was able to rationalize the death of millions for the
sake of power and pride.
Raul
=========================================================================
From: Andre Jute <andre@indigo.ie>
Subject: RE: Cancer
Date: Mon, 27 Oct 1997 22:07:34 GMT
Source: Sound Digest Archive v01.n091
Yo Gary
Comparing Frank Deutschmann to Adolf Hitler is unfair to Hitler, who,
absent the demonology of propaganda, was cultured and intelligent whereas
Deutschmann is merely civilized (it means nothing more than that he lives
in a city, like any peasant dispossessed of land) and superficially clever
in the style of so many with only a technical education. I see Deutchmann
rather as the Maximum Lider, El Grandioso Cigar-O-Gem, a stagey but
ultimately empty cloak, than real evil.
I am sorry that you too felt you had to leave the list. But most that is of
use on the Joelist happens in private mail between people who cannot stand
the "petty bullshit" in the public arena. If there is something you need to
know, write and I shall put you in touch with the right people.
Though I wish the good folk luck and everlasting good sound, I wonder how
long this rather expensively bought peace of the Joelist will last. The
resident gang of perverts *needs* someone to fuck over--it is their raison
d'etre--because without an outsider to rape they will either have to look
into the infinite emptiness of their own souls or start ripping into each
other. I wonder who will be the next target of their obsession.
Andre
At 9:37 am -0500 27/10/97, Markowitz, Gary wrote:
>Frank,
>
> <<I have just now, for the benefit of those who may have
>forgotten, taken the
> liberty of re-posting to the list some of Jute's earlier posts;
>I urge you
> all to read them again, and realize just how awful this cancer
>which has
> invaded our world is.
>
> These posts were written by Jute as his "Grand Re-Entrance" to
>JoeNet, after
> an alleged absence of only a few weeks; these posts were written
>without
> provocation by anyone on the list.>>
>
>
>You accuse Andre of lying, and you procede to lie about why they were
>posted. Seems to me that a bunch of people were flaming him about an
>article, and behind his back to boot. Frank, your incessant posts and
>threats are just as much of a cancer to this Joenet as anything Andre
>ever posted. If you are so incensed at his solicitation of copywrited
>material, report it to the proper authorities, don't cry like a baby to
>us and waste our bandwidth. It's amazing how someone as technically
>brilliant as you are can be such a total asshole.
>
> <<I would like to reiterate what Ron said: your private support
>is much
> appreciated, but if you really value JoeNet, your public support
>would go a
> long way to achieving what you have told me you want: a
>Jute-free JoeNet.>>
>
>Interesting choice of words, Frank. Let's have a closer look.
>
> >a Jute-free JoeNet.
>
>I wonder, did you choose them consiously, or by some kind of subconsious
>drive. Stir up any images? Anyone?
>
>By all means take it public. March in the streets. Attend the party
>rallies. We must clense and purify the FatherNet. Goosestep behind Herr
>Deutchmann, The Joenet Furher, amid cries of a "Jute-Free JoeNet".
>Heil Deutchmann!, the new Furrher. Seig Heil! We will tollerate no
>lies (unless we tell them). We believe in free speach (as long as the
>ideas agree with ours). Heil Deutchmann!
>
>Frank, you Nazi fuck, only half of the cancer is now gone, and a much
>more dangerous one is now left unchecked.
>
>I will not be part of a list that sits silently by while this happens,
>and even more contemptable are those who've displayed public support for
>his ideology.
>
>I'm outta here. Someone kindly let me know if Frank ever leaves, or
>better yet, drops dead.
>
>For those of you who are interested in my DIY record vac, please drop me
>a private line and I'll be glad to let you know of any progress I've
>made.
>
>Regards,
>
>Gary Markowitz
>MarkowitzG@nabisco.com
>------------------------------------------------------------------------
>----------------------------
>
>"Into the keyboard, thru the processor, off the NIC, past the gateway,
>nothing but Net"
Andre Jute
andre@indigo.ie
COMMUNICATION JUTE
- --we support pages for music lovers, writers and audiophiles at
http://www.foundmark.com/ComJute/ComJuteF1.html
=========================================================================
From: davidbarnett@aristotle.net (David N. Barnett)
Subject: Re: Cancer
Date: Tue, 28 Oct 1997 06:40:52 GMT
Source: Sound Digest Archive v01.n092
On Mon, 27 Oct 1997 19:32:52 -0500, Ron Bales <rbales@mail.gte.net>
wrote:
>Apparently Jute IS happy in a country where decent people can hardly own
>a fowling piece and the terrorists have mortars.
Last time I looked, the terrorists were in Ulster, which is part of
the UK, whereas Andre is in the Republic of Ireland. One island, two
different countries.
- --dnb
=========================================================================
From: Andre Jute <andre@indigo.ie>
Subject: RE: Cancer
Date: Tue, 28 Oct 1997 14:22:29 GMT
Source: Sound Digest Archive v01.n092
At 9:35 pm -0500 27/10/97, goyo wrote:
>Andre Jute wrote:
>>Yo Gary
>>
>>Comparing Frank Deutschmann to Adolf Hitler is unfair to Hitler, who,
>>absent the demonology of propaganda, was cultured and intelligent
>
>I think we should be careful with these kinds of differentiations. This
>type of categorizing of Hitler ignores the fact that that the culture and
>intelligence he had was able to rationalize the death of millions for the
>sake of power and pride.
>
>Raul
I take your point, Raul, that oversimplification is dangerous. But your
specific example is the result relativistic thinking. Objectively, Hitler
was intelligent and cultured. What he did with the intelligence and the
will is another matter, which I did not overlook; it was merely irrelevant
to my point. "Power and pride" are not quite exact either, though they
certainly come into it---I have been rereading Paul Johnson's A History of
the Modern World, which is the history of this century, and he is most
enlightening on these gangster dictatorships (Russia, Germany, Italy,
Japan) between the wars.
Andre
Andre Jute
andre@indigo.ie
COMMUNICATION JUTE
- --we support pages for music lovers, writers and audiophiles at
http://www.foundmark.com/ComJute/ComJuteF1.html
=========================================================================
From: "Gary Markowitz" <gary_m2@mailexcite.com>
Subject: Re: Cancer - it's still here
Date: Mon, 27 Oct 1997 11:39:20 -0700
Source: Sound Digest Archive v01.n091
Sorry if this is a repeat, my regular email isn't working properly.
Frank,
<<I have just now, for the benefit of those who may have forgotten, taken the
liberty of re-posting to the list some of Jute's earlier posts; I urge you
all to read them again, and realize just how awful this cancer which has
invaded our world is.
These posts were written by Jute as his "Grand Re-Entrance" to JoeNet, after
an alleged absence of only a few weeks; these posts were written without
provocation by anyone on the list.>>
You accuse Andre of lying, and you procede to lie about why they were posted. Seems
to me that a bunch of people were flaming him about an article, and behind his back
to boot. Frank, your incessant posts and threats are just as much of a cancer to
this Joenet as anything Andre ever posted. If you are so incensed at his solicitation
of copywrited material, report it to the proper authorities, don't cry like a baby
to us and waste our bandwidth. It's amazing how someone as technically brilliant
as you are can be such a total asshole.
<<I would like to reiterate what Ron said: your private support is much
appreciated, but if you really value JoeNet, your public support would go a
long way to achieving what you have told me you want: a Jute-free JoeNet.>>
Interesting choice of words, Frank. Let's have a closer look.
>a Jute-free JoeNet.
I wonder, did you choose them consiously, or by some kind of subconsious drive.
Stir up any images? Anyone?
By all means take it public. March in the streets. Attend the party rallies. We
must clense and purify the FatherNet. Goosestep behind Herr Deutchmann, The Joenet
Furher, amid cries of a "Jute-Free JoeNet". Heil Deutchmann!, the new Furrher.
Seig Heil! We will tollerate no lies (unless we tell them). We believe in free
speach (as long as the ideas agree with ours). Heil Deutchmann!
Frank, you Nazi fuck, only half of the cancer is now gone, and a much more dangerous
one is now left unchecked.
I will not be part of a list that sits silently by while this happens, and even more
contemptable are those who've displayed public support for his ideology.
I'm outta here. Someone kindly let me know if Frank ever leaves, or better yet,
drops dead.
For those of you who are interested in my DIY record vac, please drop me a private
line and I'll be glad to let you know of any progress I've made.
Regards,
Gary Markowitz
MarkowitzG@nabisco.com
- --------------------------------------------------------------------------------------------------
--
"Into the keyboard, thru the processor, off the NIC, past the gateway, nothing but
Net"
Free web-based email, Forever, From anywhere!
http://www.mailexcite.com
=========================================================================
From: =?ISO-2022-JP?B?GyRCPGNOUyEhOV1GcxsoQg==?= <CXL01514@niftyserve.or.jp>
Subject: Can I send mail?
Date: Fri, 19 Jun 1998 18:03:00 +0900
Source: Sound Digest Archive v01.n316
Dear Sir,
I am the subscriber of sound@mail.tpoint.net.
But for some reason,I can not send e-mail to this ML>
I just receive e-mail from this ML.
I enlarged the capacity of my mail box.So now I do not think
mails will be bounced due to mail box being full.
Could you make me able to send e-mail to the ML again?
If not,please let me know the reason.
Best Regards Koji/EIFL
=========================================================================
From: Scott Grammer <tubedude@cdc.net>
Subject: Re: Can I send mail?
Date: Fri, 19 Jun 1998 17:09:51 -0400
Source: Sound Digest Archive v01.n317
$B
> Dear Sir,
> I am the subscriber of sound@mail.tpoint.net.(snip)
Greetings, Koji!
Scott Grammer.
=========================================================================
From: "Daniel J. Marshall" <danmarshall@worldnet.att.net>
Subject: Re: Can someone explain Qloss to me?
Date: Mon, 08 Jun 1998 09:36:49 -0700
Source: Sound Digest Archive v01.n305
Hi Johannes,
From memory, and in general terms, Ql is composed of three components,
losses from air leaks, internal frictional panel losses (from flexure)
and, thirdly, frictional losses in the port. So, it is important to
make sure the enclosure is well sealed and well braced. If the
enclosure is made from a porous material, the interior should be sealed
with shellac. (Particle board is much more porous than one would
think). I don't think the port losses are very significant except for
very small diameter ports, or when they are partially obstructed (keep
any stuffing and the backwall away form the internal port opening). In
some cases, air leaks can be attributed to the speaker, e. g., through a
porous surround, through the spider (for front vented units), around the
speaker mounting surface and around the tweeter in some of the coaxial
units like the Altec 604 type. All non-glued mating surfaces exposed to
the exterior should be gasketed.
The effect of Ql is glossed over in everything I have read and is
assumed to be "typically 7". I have never seen anything written about
how to deal with it effectively. It seems to be one factor in the TS
design approach that is not easily dealt with upfront, i. e., before the
design is implemented. I posted a query in rec.audio.tech to Dick
Pierce, in an attempt to get him to comment in detail on how he deals
with Ql, especially "before the fact". He did not respond.
Not having come across anything particularly relevant in the literature,
some time ago, to specifically to investigate the effect of Ql, I
implemented the TS equations in a spreadsheet which is capable of
plotting frequency response for any specified value of Ql. Also, it has
a selectable mode which simultaneously displays the frequency response
plots of a given design for eight integer values of Ql from 4 through 11
(in different colors). When the frequency response of a given design is
displayed for these eight different values of Ql, the importance of Ql
becomes quite apparent. Ql has a very considerable effect on the low
end response. Values lower than 7 will cause a rolloff in the very low
frequencies which can be quite dramatic. igh values can cause
considerable peaking in the response on the very low end. Also, it is
possible to optimize the other enclosure parameters for a given value of
Ql. The problem is in determining the value of Ql you will end up with
before implementing the design. So, to successfully accomplish this
would require two, or perhaps more, reiterations.
Also, the effects of room boost, which are related to speaker placement,
also comes into play and must be reconed with. Some argue that typical
values of room boost are more closely complementary to 2nd order
(sealed) system rolloff and prefer them for that reason. I have
observed that the very low frequency response generally seems to be
better than the frequency response specifications would predict.
So, perhaps it could be speculated that what you are experiencing is
either a high Ql, or excessive room boost, or perhaps a combination of
the two. This could lead to a large peak(s) in the low frequency
response which likely would result in an underdamped sounding bass. If
you have calibrated measurng equipment, you could take the enclosure
outside, place it on its back with a microphone suspended over it and
measure its frequency response, then adjust the port tuning for flat
response. Then repeat the measurement in its normal placement in the
house. Then you could better define which factor is attributable to
what. (Or, there are some simple software programs which could be used
to determine the room boost). OTOH, you could just tune the port
frequency down to where it sounds best, as you have already done, and
not sweat the details. I think this is what most do.
Dan Marshall
Johannes S. Chiu wrote:
>
> Hi all,
>
> I am still trying to tune the ports in my bassbins. However, from
> various trial and errors, it seems I always end up liking longer
> ports than what most Small-Thiele simulations would prescribe. My
> current thinking is that the usual Qloss factor of 7 does not apply
> to my system. Can someone here explain to me what this Qloss factor
> is, what determines it, and how it relates to the tuning freq. of
> the box?
>
> --
> Johannes S. Chiu
> jschiu@ctr.columbia.edu
> Columbia University
> New York City
=========================================================================
From: "Daniel J. Marshall" <danmarshall@worldnet.att.net>
Subject: Re: Can someone explain Qloss to me?
Date: Mon, 08 Jun 1998 09:38:34 -0700
Source: Sound Digest Archive v01.n305
Hi Johannes,
From memory, and in general terms, Ql is composed of three components,
losses from air leaks, internal frictional panel losses (from flexure)
and, thirdly, frictional losses in the port. So, it is important to
make sure the enclosure is well sealed and well braced. If the
enclosure is made from a porous material, the interior should be sealed
with shellac. (Particle board is much more porous than one would
think). I don't think the port losses are very significant except for
very small diameter ports, or when they are partially obstructed (keep
any stuffing and the backwall away form the internal port opening). In
some cases, air leaks can be attributed to the speaker, e. g., through a
porous surround, through the spider (for front vented units), around the
speaker mounting surface and around the tweeter in some of the coaxial
units like the Altec 604 type. All non-glued mating surfaces exposed to
the exterior should be gasketed.
The effect of Ql is glossed over in everything I have read and is
assumed to be "typically 7". I have never seen anything written about
how to deal with it effectively. It seems to be one factor in the TS
design approach that is not easily dealt with upfront, i. e., before the
design is implemented. I posted a query in rec.audio.tech to Dick
Pierce, in an attempt to get him to comment in detail on how he deals
with Ql, especially "before the fact". He did not respond.
Not having come across anything particularly relevant in the literature,
some time ago, to specifically to investigate the effect of Ql, I
implemented the TS equations in a spreadsheet which is capable of
plotting frequency response for any specified value of Ql. Also, it has
a selectable mode which simultaneously displays the frequency response
plots of a given design for eight integer values of Ql from 4 through 11
(in different colors). When the frequency response of a given design is
displayed for these eight different values of Ql, the importance of Ql
becomes quite apparent. Ql has a very considerable effect on the low
end response. Values lower than 7 will cause a rolloff in the very low
frequencies which can be quite dramatic. Higher values can cause
considerable peaking in the response on the very low end. Also, it is
possible to optimize the other enclosure parameters for a given value of
Ql. The problem is in determining the value of Ql you will end up with
before implementing the design. So, to successfully accomplish this
would require two, or perhaps more, iterations.
Also, the effects of room boost, which are related to speaker placement,
also comes into play and must be reconed with. Some argue that typical
values of room boost are more closely complementary to 2nd order
(sealed) system rolloff and prefer them for that reason. I have
observed that the very low frequency response generally seems to be
better than the frequency response specifications would predict.
So, perhaps it could be speculated that what you are experiencing is
either a high Ql, or excessive room boost, or perhaps a combination of
the two. This could lead to a large peak(s) in the low frequency
response which likely would result in an underdamped sounding bass. If
you have calibrated measurng equipment, you could take the enclosure
outside, place it on its back with a microphone suspended over it and
measure its frequency response, then adjust the port tuning for flat
response. Then repeat the measurement in its normal placement in the
house. Then you could better define which factor is attributable to
what. (Or, there are some simple software programs which could be used
to determine the room boost). OTOH, you could just tune the port
frequency down to where it sounds best, as you have already done, and
not sweat the details. I think this is what most do.
Dan Marshall
Johannes S. Chiu wrote:
>
> Hi all,
>
> I am still trying to tune the ports in my bassbins. However, from
> various trial and errors, it seems I always end up liking longer
> ports than what most Small-Thiele simulations would prescribe. My
> current thinking is that the usual Qloss factor of 7 does not apply
> to my system. Can someone here explain to me what this Qloss factor
> is, what determines it, and how it relates to the tuning freq. of
> the box?
>
> --
> Johannes S. Chiu
> jschiu@ctr.columbia.edu
> Columbia University
> New York City
=========================================================================
From: "Johannes S. Chiu" <jschiu@ctr.columbia.edu>
Subject: Can someone explain Qloss to me?
Date: Mon, 8 Jun 1998 10:45:35 -0400 (EDT)
Source: Sound Digest Archive v01.n305
Hi all,
I am still trying to tune the ports in my bassbins. However, from
various trial and errors, it seems I always end up liking longer
ports than what most Small-Thiele simulations would prescribe. My
current thinking is that the usual Qloss factor of 7 does not apply
to my system. Can someone here explain to me what this Qloss factor
is, what determines it, and how it relates to the tuning freq. of
the box?
- --
Johannes S. Chiu
jschiu@ctr.columbia.edu
Columbia University
New York City
=========================================================================
From: "Greg Monfort" <wingracer@email.msn.com>
Subject: Re: Can someone explain Qloss to me?
Date: Mon, 8 Jun 1998 12:57:50 -0400
Source: Sound Digest Archive v01.n305
>Hi all,
>
>I am still trying to tune the ports in my bassbins. However, from
>various trial and errors, it seems I always end up liking longer
>ports than what most Small-Thiele simulations would prescribe.
=============
Increasing port length lowers box tuning. Maybe you just prefer the
sound of lower tuning than standard T/S alignments?
=============
My
>current thinking is that the usual Qloss factor of 7 does not apply
>to my system. Can someone here explain to me what this Qloss factor
>is, what determines it,
=============
Quoted from BoxPlot Help screen:
"Q7,Ql
"Q7 is the Q due to leakage loss in the box. This parameter cannot
be measured before the box is built so an initial guess of 7 is
used. A prefect vented box would have a very high Q ( 15). A leaky
box will have a low Q (3). BOXPLOT requires a Q of at least 3 in
order to work properly. Even though you are building a vented box
(It has a big hole in it) the vent must be the only hole. Other air
leaks in the box do not add to the main vent area, instead they act
to decrease the Q of the tuned system. This has the effect of
altering the resultant frequency response usually in an undesirable
way."
"In order to achieve a high Q, the box must be completely sealed
except for the vent. I recommend running a bead of silicone around
every seam inside the box. The front speaker board should also be
sealed with a bead of silicone before it is installed. The speaker
itself should be mounted with a gasket or a bead of silicone around
its perimeter."
Copyright 1992-1996 Rick Carlson, All rights reserved
============
and how it relates to the tuning freq. of
>the box?
============
For a given tuned frequency/port volume, box losses would be the
same as increasing box volume. This will reduce port volume.
GM
=========================================================================
From: "Lynn T. Olson" <lynno@teleport.com>
Subject: Re: Can someone explain Qloss to me?
Date: Mon, 8 Jun 1998 13:31:26 -0700
Source: Sound Digest Archive v01.n306
>I am still trying to tune the ports in my bassbins. However, from
>various trial and errors, it seems I always end up liking longer
>ports than what most Small-Thiele simulations would prescribe. My
>current thinking is that the usual Qloss factor of 7 does not apply
>to my system. Can someone here explain to me what this Qloss factor
>is, what determines it, and how it relates to the tuning freq. of
>the box?
>
>--
>Johannes S. Chiu
>jschiu@ctr.columbia.edu
>Columbia University
>New York City
Ql is very troublesome to get above 7; in practice, with many drivers and
enclosures, effective values range from 3 to 5, with 7 seen very rarely.
This term appears when you work with a Theile-Small "test box" to determine
the compliance of the driver; it has to be accounted for the equations in
order to accurately determine the Vas of the driver. What is it, anyway?
In practice, it is the sum of all box leaks. You might think "so what", but
rest assured, in a high-Q system (like all vented systems), a very small
leak causes substantial shifts in system parameters. How small a leak? Very
small, such as a slightly porous dust-cap, tiny voids in the glue of the
enclosure, even leakage through the cone surround!
Getting Ql higher is a major pain; back my Audionics days, I did things
like seal the dust-cap (which wrecks the large-signal response due to air
rushing around the voice-coil), coat the surround with a thin layer of
glue, and use putty around all of the interior joins in the test box. In
other words, things you'd never do in production. And I never managed to
get Ql in that test box any higher than 7, maybe 7.5 on a good day with a
tailwind. Production cabinets (like the Audionics T-52) typically measured
from 3.5 to 5; so in aligning the system for production, I had to aim for
the mean value of Ql and make some assumptions about speaker cable
resistance and amplifier damping factor. All in a days' work designing a
commercial vented system.
(Going with a non-standard alignment like a 4th-order Bessel made this a
bit of extra fun, although in practice the Bessel turns out to be less
touchy about system tuning errors than a standard QB3 - B4 - C4 alignment.
Too bad the generic computer software programs don't show group-delay
curves for custom alignments; that's the easiest way to roll your own
non-standard Bessel high-pass function. Otherwise you get to do a lot of
tedious approximations. I still take a little pride in designing the
Audionics T-52 with a 4th-order Bessel alignment back in 1976. The BL4
equation is in Part IV, Appendices, of the original Small article in the
AES Journal.)
The Ql discussion is what separates the know-it-alls who are faking it from
the guys who have paid their dues with Theile-Small theory, back in the
days when the computer wasn't around to do all the thinking. Having found
out the hard way just how sensitive any vented system (conventional,
bandpass, etc.) is to shifts in source impedance and hard-to-quantify
losses of many kinds, I don't like using them unless the drivers just won't
work with anything else.
I should add that the highly reactive load of vented speakers makes the
distortion of SE amps skyrocket beyond the resistive-load figures, on the
order of 3 to 5 times higher than the specified 8 ohm distortion spec. The
only mitigating factor is that the four reactance maxima (regions of
maximum slope on the impedance curves) are all at pretty low frequencies.
This where "cheating" by deliberately adding vent resistance (fiberfill in
the vent, or drinking straws, etc.) can prove useful by detuning the entire
alignment in the direction of a resistive-vent system. The F3 is much
higher of course, similar to a closed-box (no free lunch folks), but the
system is much less reactive, easier to drive, and also doesn't care as
much about shifts in Qts in the driver, box loss, etc.
Not complicated, really: high-Q filters are touchy about the interface
(amp, box, and room), low-Q filters aren't. Your choice.
I like TL's myself, even if the mathematical crowd think I'm nuts. I know
enough about T/S theory to know that a great deal is swept under the rug of
simplifying approximations. Ql=7 is just one of many "assumptions"; another
is the fact that those finite box leaks mentioned earlier can insert a zero
in the response at very low frequencies, around 0.2 to 0.5 Hz. Read the
test techniques in the early AES papers very carefully, and they warn about
the presence of this zero (which is always there in real systems)
influencing the compliance measurement. Well, guess what? Having a zero at
a very low frequency means the driver cone will always be wandering around
the zero point at a 0.2 to 0.5Hz rate, a sort of breathing effect visible
on some program material. Not to mention dramatic degradation of the
group-delay response of the system at the lowest frequencies. Oh yes, did I
mention that these leaks/losses are highly nonlinear? Leaks tend to be in
one direction, so the in and out time constants are different. Crank that
one into LEAP or BOXMODEL.
To me, the T/S computer models kind of remind me of those AES articles that
start, "assuming a distortionless amplifier ..."
Lynn T. Olson
E-mail: lynno@teleport.com
Ariel Speaker Page: http://www.teleport.com/~lynno/Ariel.htm
=========================================================================
From: peterca@ento.csiro.au
Subject: Re: Can someone explain Qloss to me?
Date: Tue, 9 Jun 1998 17:28:37 +1000 (EST)
Source: Sound Digest Archive v01.n306
So I should really regard the value of 7 as about as good as I'm likely to get?
I'd like to be being realistic about my first iteration because it will
probably be the last.
I am starting to tinker with a little reflex box I am using to get some
decent radio at work. It is based on a nice old box plus a new kit of
drivers. The 6" "Response" driver has a plastic cone with carbon fibre
weave through it. (and Vifa D19 tweeter) The magnet is vented to the rear.
The dust cap is not porous and seems to be glued on well. The surround
also seems securely attached and non-porous rubber. I will use gaskets and
attempt to seal in the driver tightly. The box has varnish inside and glue
along the seams so I don't think the woodwork should be leaky but I was
planning to go over it anyway when I glue in extra bracing. The extra
bracing should be overthetop for a small box which is already sturdier than
most commercial boxes. The port diameter is adequate for the driver
according to the "cookbook".
I can't think of any other leakage sites. I don't think the port would
count as unusually resistive. I'll keep its opening clear of stuffing etc.
I'll also keep the rear of the driver unobstructed. Does filling
elsewhere in the box contribute to Ql?
Should I still work on the assumption that Ql might be significantly less
than 7 and no chance of it being much more than 7?
Dr. Peter Campbell (peterca@ento.csiro.au)
Div. Entomology, C.S.I.R.O. Ph.61-2-62464053 or -62464158 (w)
Box 1700 Canberra A.C.T. 2601 61-2-62516213 (h)
Australia 61-2-62464173 (fax)
=========================================================================
From: "Lynn T. Olson" <lynno@teleport.com>
Subject: Re: Can someone explain Qloss to me?
Date: Tue, 9 Jun 1998 14:20:13 -0700
Source: Sound Digest Archive v01.n307
>Should I still work on the assumption that Ql might be significantly less
>than 7 and no chance of it being much more than 7?
Yes. Aim for Ql being between 5 and 6 in the real world. Adjust the tuning
for smoothest group-delay vs freq response and that will also decrease
sensitivity to misalignment. Misaligned tuning is why "bass-reflexes" got a
bad rep back in the Fifties (in the days before Theile published his first
paper in Oz in 1963). Avoid the "extended bass shelf" alignments which have
wretched group-delay response.
Lynn T. Olson
E-mail: lynno@teleport.com
Ariel Speaker Page: http://www.teleport.com/~lynno/Ariel.htm
=========================================================================
From: Thomas Danley <Tom@ppci.com>
Subject: Re: Can someone explain Qloss to me?
Date: Wed, 10 Jun 1998 20:08:44 -0500
Source: Sound Digest Archive v01.n308
Lynn T. Olson wrote:
>
snip>
Adjust the tuning
> for smoothest group-delay vs freq response and that will also decrease
> sensitivity to misalignment. Misaligned tuning is why "bass-reflexes" got a
> bad rep back in the Fifties (in the days before Theile published his first
> paper in Oz in 1963). Avoid the "extended bass shelf" alignments which have
> wretched group-delay response.
>
> Lynn T. Olson
Hi all
Actually, the magnitude of group delay is related to the frequency and
steepness of the roll off slope. The steeper the slope at any given cut
off frequency, the greater the group delay near cutoff.
That is why high order band pass's have the worst group delay followed
by the simple band pass, vented, conventionally tuned and sealed finally
having the least delay.
A stepped down alignment has a more gradual roll off and has
(at least all the leap models I tried) LESS group delay than a vented
system with the same final cutoff.
Best Regards,
Thomas Danley
Intersonics Technology Corp
=========================================================================
From: "Lynn T. Olson" <lynno@teleport.com>
Subject: Re: Can someone explain Qloss to me?
Date: Thu, 11 Jun 1998 13:30:06 -0700
Source: Sound Digest Archive v01.n309
>>Avoid the "extended bass shelf" alignments which have
>> wretched group-delay response.
>>
>> Lynn T. Olson
>A stepped down alignment has a more gradual roll off and has
>(at least all the leap models I tried) LESS group delay than a vented
>system with the same final cutoff.
>Best Regards,
>
>Thomas Danley
>Intersonics Technology Corp
I was referring to the "extended bass shelf" alignments that are commonly
recommended to squeeze a few more Hz out of a too-small box. There is very
large increase in group delay right at the very sharp corner frequency, and
usually some odd ripples where the "shelf" stepdown begins as well. In a
sense, a 4th-order Bessel alignment is the opposite; much higher cutoff,
but no sudden sharp peaks in the group-delay function.
This choice between transient response and bass extension is a typical
Theile/Small tradeoff, and seen in closed-box alignments as well, where Qts
= 1.1 to 1.2 typically gives the maximum extension for a given box volume,
and Qts values lower than 0.7 give the best transient response.
Lynn T. Olson
E-mail: lynno@teleport.com
Ariel Speaker Page: http://www.teleport.com/~lynno/Ariel.htm
=========================================================================
From: Ron Bales <rbales@gte.net>
Subject: Can the 810 be tamed?
Date: Mon, 18 May 1998 09:14:42 -0400
Source: Sound Digest Archive v01.n282
Has anyone tried this monster in SE audio?
I've got the old VALVES with Paul Joppa's commentary on Doc's 805 amp and
on doing a Class A2 amp in general.
I know where there are a pair in some ancient ham gear along with sockets
and HV supply.
Might keep a fellow off the streets for awhile.
ROn
=========================================================================
From: Jim de Kort <jdekort@xs4all.nl>
Subject: Capacitances
Date: Mon, 08 Sep 1997 03:07:42 +0200
Source: Sound Digest Archive v01.n015
Hi,
While we're on the topic of interelctrode capactities...
Does anyone out there know the Cgp Cgc and Cpc values of a VT52???
Jim de Kort
jdekort@xs4all.nl
- -----------------------------------------------
For DHT tube data and tubes
for sale, check out the
PhaetoN HomePage
http://www.xs4all.nl/~jdekort/
- -----------------------------------------------
=========================================================================
From: BART <bartonw@ozemail.com.au>
Subject: RE: Capacitances
Date: Tue, 9 Sep 1997 09:49:52 +1000
Source: Sound Digest Archive v01.n016
Jim de Kort asked:
>
While we're on the topic of interelctrode capactities...
Does anyone out there know the Cgp Cgc and Cpc values of a VT52???
>
Can't help you Jim. I am interested in this too. In fact all the figures for the VT52. I am not sure
they are exactly the same as the 45.
Can someone help with the capacitance info for the 211 and 300B also?
I only have this for the 2A3 which is:
Cgp 16.5, Cgc 7.5 and Cpc 5.5
Bart
=========================================================================
From: Chris Galbraith <chrisg@ducker.com>
Subject: Capacitor characteristics--this is very intriguing
Date: Wed, 4 Mar 1998 13:43:26 -0500
Source: Sound Digest Archive v01.n207
With the recent thread on dielectric absorption, etc...I'm wondering if
anyone can explain some capacitor characteristics or point to a good
source to *honestly* understand what is happening inside these
devices--I mean, as far as measurements go, which I take with a grain of
salt, but...
We have dielectric absorption.
My particular interest lately has been trying to decipher how ESR,
dissipation factor, ripple current, etc. relate to eachother--and what
are typical merits, etc. of different capacitor types in these terms.
For instance, looking at some electrolytics aimed at audio applications
(Nichicon Muse, Panasonic HF[I think], Elna Cerafines, Black Gates,
etc), we are given numbers for ESR (is this the tangent of ?, typically
.08 for 'low ESR' 100v caps), then dissipation factors anywhere from 8
to 20%. Also, Digikey lists ripple current for many of the Panasonic
caps.
I do not have a clear understanding of what all these things mean in
relation to eachother, let alone by themselves. To make matters a
little more confusing, not all manufacturers provide the same type of
data, making apple-to-apple comparisons impossible on paper.
Of course this is mostly academic, but I'd sure like to know, or find a
good source to read up on these fascinating devices!!
Until then, I'll stick with old oils and Cerafines. :)
- -Chris
=========================================================================
From: Miguelito <mbarrio@midway.uchicago.edu>
Subject: Re: Capacitor characteristics--this is very intriguing
Date: Wed, 4 Mar 1998 14:57:38 -0600 (CST)
Source: Sound Digest Archive v01.n207
> For instance, looking at some electrolytics aimed at audio applications
> (Nichicon Muse, Panasonic HF[I think], Elna Cerafines, Black Gates,
> etc), we are given numbers for ESR (is this the tangent of ?, typically
> .08 for 'low ESR' 100v caps), then dissipation factors anywhere from 8
> to 20%. Also, Digikey lists ripple current for many of the Panasonic
> caps.
ESR stands for "Equivalent Series Resistance" and it's due to the fact that
the dielectrics used don't have infinite resistance (no dielectric on the
face of the earth does!). That is, if you put a voltage difference you will
have a small current flow. This is particularly bad with electrolytics
mostly because (AFAIK) the isolation between anode and electrolytic
solution is provided by a thin oxide layer on the anode.
I think it's quite obvious that ESR and dissipation factor (or equivalently
dielectric relaxation time) have nothing to do with each other. One is the
(small) conductivity of the dielectric and the other the time it takes for
the dielectric to relax (the units are different also).
Miguel
=========================================================================
From: Miguelito <mbarrio@midway.uchicago.edu>
Subject: Re: Capacitor characteristics--this is very intriguing
Date: Wed, 4 Mar 1998 16:35:46 -0600 (CST)
Source: Sound Digest Archive v01.n207
C'est moi again,
I think I made a gross mistake. Since ESR means *series* resistance, it
probably refers to the fact that a capacitor will have some resistive
behaviour in the sense that, if we want to pass current very fast through
it, instead of acting like a "short" it will have some resistance. This
would be modeled by a impedance of the form:
Z(w)= Resr + 1/i*w*C
(in freq. domain) which means that at very high frequencies the device
looks resistive. Sorry about that. BTW, I'm sure that there's an inductive
term there as well, all components have a bit of everything, however small,
no? :-)
As far as relaxation time is concerned, I think that my point of it being
unrelated to ESR still holds.
Miguel
- --
Miguel Barrio "I think I've lived
mailto:miguelito@pobox.com someone else's life."
http://pobox.com/~miguelito -- Pablo Neruda
=========================================================================
From: Guy Pelletier <audio@colba.net>
Subject: Re: Capacitor characteristics--this is very intriguing
Date: Wed, 04 Mar 1998 20:03:01 -0500
Source: Sound Digest Archive v01.n208
This is a multi-part message in MIME format.
- --------------85DD419ED3A6A9D678FE585C
Content-Type: multipart/alternative; boundary="------------A7BB800A84B47FB018847D91"
- --------------A7BB800A84B47FB018847D91
Content-Type: text/plain; charset=us-ascii
Content-Transfer-Encoding: 7bit
Chris Galbraith wrote:
> With the recent thread on dielectric absorption, etc...I'm wondering if
> anyone can explain some capacitor characteristics or point to a good
> source to *honestly* understand what is happening inside these
> devices--I mean, as far as measurements go, which I take with a grain of
> salt, but...
> -Chris
Hi Joe's and Chris,
I garanty you nothing, but you could try to contact Mr. Denis Ouellet from
Solen electronics Inc. for good books, sources or maybe answers to your
questions.
solen@quebec.net
Solen's main menu
Good luck,
- --------------A7BB800A84B47FB018847D91
Content-Type: text/html; charset=us-ascii
Content-Transfer-Encoding: 7bit
<HTML>
Chris Galbraith wrote:
<BLOCKQUOTE TYPE=CITE>With the recent thread on dielectric absorption,
etc...I'm wondering if
<BR>anyone can explain some capacitor characteristics or point to a good
<BR>source to *honestly* understand what is happening inside these
<BR>devices--I mean, as far as measurements go, which I take with a grain
of
<BR>salt, but...
<BR>-Chris</BLOCKQUOTE>
Hi Joe's and Chris,
<P>I garanty you nothing, but you could try to contact Mr. Denis Ouellet
from Solen electronics Inc. for good books, sources or maybe answers to
your questions.<A HREF="mailto:solen@quebec.net"></A>
<P><A HREF="mailto:solen@quebec.net">solen@quebec.net</A>
<BR><A HREF="http://www.quebec.net/solen/">Solen's main menu</A>
<P>Good luck,</HTML>
- --------------A7BB800A84B47FB018847D91--
- --------------85DD419ED3A6A9D678FE585C
Content-Type: text/x-vcard; charset=us-ascii; name="vcard.vcf"
Content-Transfer-Encoding: 7bit
Content-Description: Card for Guy Pelletier
Content-Disposition: attachment; filename="vcard.vcf"
begin: vcard
fn: Guy Pelletier
n: Pelletier;Guy
org: Préférence Audio
adr: 13-835, Industriel;;;St-Jean;Québec;J3B 4S9;Canada
email;internet: audio@colba.net
title: Loudspeaker designer
tel;work: (514) 349-0021
x-mozilla-cpt: ;11856
x-mozilla-html: TRUE
version: 2.1
end: vcard
- --------------85DD419ED3A6A9D678FE585C--
=========================================================================
From: Paul Joppa <pdj@ISDNseattle.net>
Subject: Re: Capacitor characteristics--this is very intriguing
Date: Wed, 04 Mar 1998 21:58:54 -0800
Source: Sound Digest Archive v01.n208
Miguelito wrote:
>
> C'est moi again,
>
> I think I made a gross mistake. Since ESR means *series* resistance, it
> probably refers to the fact that a capacitor will have some resistive
> behaviour in the sense that, if we want to pass current very fast through
> it, instead of acting like a "short" it will have some resistance. This
> would be modeled by a impedance of the form:
>
> Z(w)= Resr + 1/i*w*C
>
> (in freq. domain) which means that at very high frequencies the device
> looks resistive. Sorry about that.
Actually, I think you're right both times. At any frequency the
resistive component can be interpreted as series or parallel -
your choice. ESR is *not* constant at all frequencies, so it is
specified at a frequency. Source can be both leakage and wire
loss.
- -Paul Joppa
=========================================================================
From: Torsten.Loesch@enhar-ha.nthames.nhs.uk
Subject: Re(2): Capacitor characteristics--this is very intriguing
Date: Thu, 5 Mar 1998 13:13:29 +0000
Source: Sound Digest Archive v01.n208
Hi Miguel,
For better understanding of what happens in Capacitors,
may I suggest Walt Jungs and Rob marches article from
AUDIO.
It is on line at the REL-Capacitors site,
www.capacitors.com
Sorry, very busy, gotta go.
Later Thorsten
=========================================================================
From: Michel Paquette <paqm01@GEL.USherb.CA>
Subject: Re: Capacitor hysteresis effect
Date: Tue, 3 Mar 1998 15:01:01 -0400
Source: Sound Digest Archive v01.n206
Per Arne said:
>
>It was almost like the bad capacitors were trying to uphold a small voltage
>across it, like a rechargeable battery.
>
>What property in a capacitor would be guilty of such an imperfection?
>
I think what you are talking about is dielectric absorption. I don't know
much about it though...
Michel
=========================================================================
From: Miguelito <mbarrio@midway.uchicago.edu>
Subject: Re: Capacitor hysteresis effect
Date: Tue, 3 Mar 1998 17:51:14 -0600 (CST)
Source: Sound Digest Archive v01.n206
> >It was almost like the bad capacitors were trying to uphold a small voltage
> >across it, like a rechargeable battery.
> >
> >What property in a capacitor would be guilty of such an imperfection?
It's due to polarization of the dielectric that separates the two
conductors that form the capacitor.
When there's a voltage difference applied to the cap an electric field is
created between the conductors. A dielectric in an electric field gets
polarized. This means that positive charges are pulled in the direction of
the electric field and negative charges are pulled in the opposite
direction (in fact, this effect is what make the capacitance increase if
the dielectric is highly polarizable). So it's all fine for now.
Assume now that you've charged the capacitor with a battery and now you
have the charged capacitor (not connected to the battery anymore, that is).
If you measure the voltage across the capacitor you will measure the
battery's voltage. Now short the terminals for a very short time. You will
see that the voltage goes to zero and then goes back to some small positive
value! The reason for this is that the polarized dielectric doesn't respond
as fast and thus, when it 'relaxes', a positive voltage is left in the
capacitor.
This "relaxation time" will be different for different dielectrics, mylar,
polypropylene, polystyrene and teflon have decreasing relaxation times,
teflon being the one with fastest response.
Hope this is clear.
Miguel
- --
Miguel Barrio "He who knows others is wise.
mailto:miguelito@pobox.com He who knows himself is
http://pobox.com/~miguelito enlightened." -- Laozi
=========================================================================
From: "P.A. & M. Almeflo" <sd@ljusdal.se>
Subject: Capacitor hysteresis effect
Date: Tue, 3 Mar 1998 19:00:03 +0100
Source: Sound Digest Archive v01.n206
Hello everybody.
Let me tell you an off topic story about a capacitor in a hydraulic servo
circuit. The final question is on the topic, though.
A few years ago I worked with the development of an analog hydraulic servo
system.
The regulator was built with op-amps and a filter for a phase advancing
circuit was used to compensate overshoots caused by the phase response of
the hydraulic valve. (It was a variation of the D-portion in a
PID-regulator.)
Anyway, the introduction of the capacitor in this circuit was followed by a
very distinct hysteresis effect. We could measure a couple of tenths of
mms of uncertainty in the position accuracy, while without this capacitor
the variation was well below 1/100mm.
We tried many different capacitor makes and types. The only type we could
find at that time in the right size that worked was an EVOX polypropylene
capacitor. The hysteresis effect was now completely unmeasurable.
It was almost like the bad capacitors were trying to uphold a small voltage
across it, like a rechargeable battery.
What property in a capacitor would be guilty of such an imperfection?
Best regards,
Per Arne Almeflo
=========================================================================
From: Ed Fallon <efalon@wolfenet.com>
Subject: Re: Capacitor hysteresis effect
Date: Wed, 04 Mar 1998 08:05:32 -0800
Source: Sound Digest Archive v01.n207
P.A.
This sounds like the classic definition of capacitor dielectric absorption or
DA. I believe polyproplene has very good DA specs where electrolytics are
generally poor.
Ed
P.A. & M. Almeflo wrote:
> Hello everybody.
>
> Let me tell you an off topic story about a capacitor in a hydraulic servo
> circuit. The final question is on the topic, though.
>
> A few years ago I worked with the development of an analog hydraulic servo
> system.
> The regulator was built with op-amps and a filter for a phase advancing
> circuit was used to compensate overshoots caused by the phase response of
> the hydraulic valve. (It was a variation of the D-portion in a
> PID-regulator.)
> Anyway, the introduction of the capacitor in this circuit was followed by a
> very distinct hysteresis effect. We could measure a couple of tenths of
> mms of uncertainty in the position accuracy, while without this capacitor
> the variation was well below 1/100mm.
> We tried many different capacitor makes and types. The only type we could
> find at that time in the right size that worked was an EVOX polypropylene
> capacitor. The hysteresis effect was now completely unmeasurable.
>
> It was almost like the bad capacitors were trying to uphold a small voltage
> across it, like a rechargeable battery.
>
> What property in a capacitor would be guilty of such an imperfection?
>
> Best regards,
> Per Arne Almeflo
=========================================================================
From: SSell71096@aol.com
Subject: Re: Re: Capacitor hysteresis effect
Date: Wed, 4 Mar 1998 12:21:37 -0500 (EST)
Source: Sound Digest Archive v01.n207
>This sounds like the classic definition of capacitor dielectric >absorption
or DA. I believe polyproplene has very good DA >specs where electrolytics
are generally poor.
Are there are caps out there that are as good or better than polypro? How do
Teflon or oil compare?
=========================================================================
From: "Sellek, Grant (TSA)" <Grant.Sellek@roads.sa.gov.au>
Subject: RE: Capacitor hysteresis effect - paper in oils?
Date: Thu, 05 Mar 1998 11:11:47 +1030
Source: Sound Digest Archive v01.n208
>From: Ed Fallon[SMTP:efalon@wolfenet.com]
>This sounds like the classic definition of capacitor dielectric absorption or
>DA. I believe polyproplene has very good DA specs where electrolytics are
>generally poor.
And how would the fabled paper in oil foil cap rate in this area of
performance? I am still trying to understand the basis of its sonic
reputation. Is it because it electrically performs poorly, but in a
nice-sounding way?
Grant Sellek
Adelaide, Australia
grant.sellek@roads.sa.gov.au
>P.A. & M. Almeflo wrote:
>
.....
>> Anyway, the introduction of the capacitor in this circuit was followed by a
>> very distinct hysteresis effect...... The only type we could
>> find at that time in the right size that worked was an EVOX polypropylene
>> capacitor. The hysteresis effect was now completely unmeasurable.
>>
>> It was almost like the bad capacitors were trying to uphold a small voltage
>> across it, like a rechargeable battery.
=========================================================================
From: Roscoe Primrose <roscoe@aiko.com>
Subject: Capacitor identification...
Date: Sat, 29 Aug 1998 21:17:56 -0400
Source: Sound Digest Archive v01.n408
I've got a whole bunch of 600V caps, values from .001 to .1 uF, but I
have no idea what type of caps they are...
They're labeled Argonne, JCP-TNN-R, made in Japan.
These are probably from the 60s or early 70s.
Anybody have any idea what they are?
TIA
Peace
- --
Roscoe Primrose
- -- mailto:roscoe@aiko.com -- http://www.aiko.com/roscoe --
"Once in a while you get shown the light
In the strangest of places if you look at it right." Robert Hunter
=========================================================================
From: Steve Van Osdell <svanos@toast.net>
Subject: Capacitor question
Date: Fri, 23 Jan 1998 18:52:50 -0600
Source: Sound Digest Archive v01.n169
When can a non-polarized film cap be used where there was a poloarized
lytic? Also, are little .05 400V oil caps polarized?
I have a unit I'm trying to fix (learning as I go). It is a receiver.
First, one of the 6BQ5 tubes gets cherry red on the plates, and then there
is a problem with one of the little 6UA8 tubes that are located between
each IF stage. When you turn the selector knob from AUX to AM, I see what
looks like 'lightning' inside the first 6UA8 tube. But it tests fine.
Any ideas where to start. I'm getting no sound (no hum, no static, no
nothing) out of the speakers.
Thanks, Steve
=========================================================================
From: Torsten.Loesch@FinanceManager.Finance.FinanceAndInformation.enhar-ha.nthames.nhs.uk
Subject: Re: Capacitor question
Date: Sat, 24 Jan 1998 18:20:42 +0000
Source: Sound Digest Archive v01.n169
Hi,
> When can a non-polarized film cap be used where there was a poloarized
> lytic?
All the time. The other way around is not recommended though and you will
need suitable values for the Non-Polarised Cap of course.
Later Thorsten
(Sorry nothing on the other questions that would take less then a few
hours....
=========================================================================
From: evaguido <EvaGuido@iaehv.nl>
Subject: Re: Capacitor question
Date: Sun, 25 Jan 1998 22:35:08 +0100
Source: Sound Digest Archive v01.n170
At 18:52 23-1-98 -0600, Steve Van Osdell wrote:
>When can a non-polarized film cap be used where there was a poloarized
>lytic?
Always
>Also, are little .05 400V oil caps polarized?
I never saw polarized paper
>I have a unit I'm trying to fix (learning as I go). It is a receiver.
>First, one of the 6BQ5 tubes gets cherry red on the plates,
Output ?
1-Too high current
2-Oscillation
Try to swap this one with other 6BQ5s, see if the problem stays, or travels
along with the tube
>and then there
>is a problem with one of the little 6UA8 tubes that are located between
>each IF stage. When you turn the selector knob from AUX to AM, I see what
>looks like 'lightning' inside the first 6UA8 tube. But it tests fine.
Seems that grid resistors are neccessary there
>Any ideas where to start. I'm getting no sound (no hum, no static, no
>nothing) out of the speakers.
That's not too much Steve
Start looking at the tubes, are they heated ? Continue with the B+, then
the cathodes of the outputs.
Then report in your next mail
Have fun, take care of B+
Guido
>Thanks, Steve
>
>
=========================================================================
From: RALPH POWER <POWER.RALPH@epamail.epa.gov>
Subject: Capacitor question
Date: Thu, 29 Jan 1998 12:37:56 -0500
Source: Sound Digest Archive v01.n175
Hi all,
Is a 3300 pf capacitor the same value as a .0033 mf capacitor ?
That's what I calculate. Am I missing something ?
This is the value usually specified in the composite RIAA network of the RCA
phono stage. Curiously the reprint of the circuit in the 1996 Angela catalog
specifies .0035 mf. Any comment about this ?
Thanks for any info.
- Ralph
=========================================================================
From: Tim Reese <reese@nmr.MGH.harvard.EDU>
Subject: Re: Capacitors
Date: Thu, 12 Mar 1998 10:25:29 -0500 (EST)
Source: Sound Digest Archive v01.n214
Miguel wrote:
>> Yeah but they're so easy to do business with. They answer the phone and
>> they take credit cards.
>
>True! I've bought some stuff from Michael Percy and I've always had great
>service from him, but having to send him a check is a real pain in the
>ass. And since my orders are usually around $50, he doesn't really pay too
>much attention to them (my first order was delayed because he didn't
>'notice' that my small check had arrived). Still, I'd buy from him and not
>TPC just because his prices are lower (and he's knoledgeable, that is, if
>you manage to talk to him!).
MP is a great source - honest, helpful, and good prices.
You might also consider (esp. those on the east coast) Tony at Handmade
Electronics. He has much of the "boutique" lines that MP carries, as
well as high-end tube sockets, specialty wire, Hammond, Magnequest,
Solo, high-end resistors, potentiometers, chassis supplies, high-end
connectors, tubes and other stuff. Inexpensive catalog and a web site.
He ships quickly, and is reasonably priced. 610-432-5732, fax
610-432-8971.
cheers tr
- ---------------------------------------------------------------
Tim Reese, MGH NMR Center reese@nmr.MGH.harvard.edu
=========================================================================
From: Tim Reese <reese@nmr.MGH.harvard.EDU>
Subject: Re: Capacitors
Date: Thu, 12 Mar 1998 13:49:46 -0500 (EST)
Source: Sound Digest Archive v01.n215
There's an ad on page 14 of issue 14 of SP -
http://www2.netcom.com/~handmade/first.html
cheers tr
- ---------------------------------------------------------------
Tim Reese, MGH NMR Center reese@nmr.MGH.harvard.edu
>At 10:25 12-03-98 -0500, Tim Reese wrote:
>>You might also consider (esp. those on the east coast) Tony at Handmade
>>Electronics. He has much of the "boutique" lines that MP carries, as
>>well as high-end tube sockets, specialty wire, Hammond, Magnequest,
>>Solo, high-end resistors, potentiometers, chassis supplies, high-end
>>connectors, tubes and other stuff. Inexpensive catalog and a web site.
>
>Where can I find his web site?
>
>Emile
=========================================================================
From: Emile Sprenger <emile.sprenger@cmg.nl>
Subject: Re: Capacitors
Date: Thu, 12 Mar 1998 19:02:45 +0100
Source: Sound Digest Archive v01.n215
At 10:25 12-03-98 -0500, Tim Reese wrote:
>You might also consider (esp. those on the east coast) Tony at Handmade
>Electronics. He has much of the "boutique" lines that MP carries, as
>well as high-end tube sockets, specialty wire, Hammond, Magnequest,
>Solo, high-end resistors, potentiometers, chassis supplies, high-end
>connectors, tubes and other stuff. Inexpensive catalog and a web site.
Where can I find his web site?
Emile
=========================================================================
From: "Brian Drought" <drought@globalnet.co.uk>
Subject: Re: Capacitors ?
Date: Thu, 25 Jun 1998 08:34:25 +0100
Source: Sound Digest Archive v01.n319
- -----Original Message-----
From: SHAMSUL Bahrin Kamarudin <shamsul.BK@innosabah.com.my>
>Hello.
>
>Just would like some opinion regarding capacitors used in loudspeaker
>crossovers.
>
>Which config sounds better for capacitors say I need to connect a 10uf
>value to the crossover .... a single value of 10uf or double 5uf connected
>parallel ?
*OR* (Throwing a spanner into the works).. a 7uf and a 3uf in parallel.I
think this may sound better as you might possibly go someway to eliminating
resonance.....
~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~
Brian Drought ICQ# - 2180069 drought@globalnet.co.uk
I've been looking for a savior in these dirty streets
Looking for a savior beneath these dirty sheets
I've been raising up my hands
Drive another nail in
Just what God needs
One more victim
Why do we crucify ourselves?
-Tori Amos
*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*
=========================================================================
From: Hartmut <Hartmut.Quaschik@mch.sni.de>
Subject: Re: Capacitors ?
Date: Thu, 25 Jun 1998 10:17:17 +0200
Source: Sound Digest Archive v01.n319
SHAMSUL Bahrin Kamarudin wrote:
> Just would like some opinion regarding capacitors used in loudspeaker
> crossovers.
>
> Which config sounds better for capacitors say I need to connect a 10uf
> value to the crossover .... a single value of 10uf or double 5uf
> connected parallel ?
My experiences with caps are from using them as coupling caps
when constructing preamps, so it may not apply to your case,
where you probably use them only in the treble part of the xover .
in hifi-terms double 5uF, because ESR is halved, I think you will
have a gain of treble and midrange clarity.
in music terms the single 10uF, as there is only one timeconstant
disturbing the music - I mean intrinsic material timeconstants
of devices here, changing device properties with time and
temperature and volume and so on. But it is not as bad as when
paralleling transistors. But when you parallel, you should
use 100% identical caps, from the same manufacturer and batch,
preferably. If you use different brands, you could suffer
a certain kind of inhomogenity revealed by long term listening,
even if you have a bettered resolution.
you do single ended, but double capped, shhh ....
best regards,
Hartmut
=========================================================================
From: SHAMSUL Bahrin Kamarudin <shamsul.BK@innosabah.com.my>
Subject: Capacitors ?
Date: Thu, 25 Jun 1998 14:29:09 +0800
Source: Sound Digest Archive v01.n319
Hello.
Just would like some opinion regarding capacitors used in loudspeaker
crossovers.
Which config sounds better for capacitors say I need to connect a 10uf
value to the crossover .... a single value of 10uf or double 5uf connected
parallel ?
Regards.
::-)
\\\///
/ _ _ \
(| (.)(.) |)
|--------.OOOo--()--oOOO.-- mailto:shamsul.BK@innosabah.com.my -|
_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/
_/ H/P: 019-8107360 TEL: 6088-244185 FAX: 6088-251679 _/
_/ http://www.innosabah.com.my _/
_/ ======================================================== _/
_/ TO BECOME A LEADING HI-TECH, PEOPLE ORIENTED FINANCIAL _/
_/ SERVICES COMPANY WHICH OFFERS WORLD CLASS _/
_/ INNOVATIVE PRODUCTS AND SERVICES _/
_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/
_/ THIS IS A | INNOSABAH SECURITIES SDN BHD (194990-K) _/
_/ COMPUTER GENERATED | 11 EQUITY HOUSE, BLOCK K, _/
_/ ELECTRONIC MAIL | SADONG JAYA, KARAMUNSING, _/
_/ AND IS DEEMED TO | 88100 KOTA KINABALU, SABAH, _/
_/ HAVE BEEN SIGNED | M A L A Y S I A _/
_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/
=========================================================================
From: evaguido <EvaGuido@iaehv.nl>
Subject: Re: Capacitors ?
Date: Thu, 25 Jun 1998 21:29:51 +0200
Source: Sound Digest Archive v01.n320
At 08:34 25-6-98 +0100, Brian Drought wrote:
>
>-----Original Message-----
>From: SHAMSUL Bahrin Kamarudin <shamsul.BK@innosabah.com.my>
>
>>Hello.
>>
>>Just would like some opinion regarding capacitors used in loudspeaker
>>crossovers.
>>
>>Which config sounds better for capacitors say I need to connect a 10uf
>>value to the crossover .... a single value of 10uf or double 5uf connected
>>parallel ?
>
>*OR* (Throwing a spanner into the works).. a 7uf and a 3uf in parallel.I
>think this may sound better as you might possibly go someway to eliminating
>resonance.....
Maybe, but depends on the construction of the caps
Try that by connecting the cap across a decent amplifier, and sweep it
through the audio band, and listen (!) to it
I learned that from Peter Qvortrup, Audio Note UK
Guido
>~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~
>Brian Drought ICQ# - 2180069 drought@globalnet.co.uk
>
> I've been looking for a savior in these dirty streets
> Looking for a savior beneath these dirty sheets
> I've been raising up my hands
> Drive another nail in
> Just what God needs
> One more victim
> Why do we crucify ourselves?
> -Tori Amos
>
>*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*
>
>
>
>
=========================================================================
From: Edgar Faulkner <efaulkne@wsunix.wsu.edu>
Subject: Capacitor sorce
Date: Mon, 1 Dec 1997 14:10:49 -0800 (PST)
Source: Sound Digest Archive v01.n122
I need a sorce for various caps, Cerifine and Hoveland mostly. My bookmark
to the "The long awaited resource directory!" ain't connecting.
______________________________
Ed Faulkner \ through a child's eyes
Instructional Support Services \ sky is blue
Washington State University \ grass is green
Pullman, WA 99164 \ I want to see again
(509) 335-7566 \
efaulkne@wsu.edu. \_________________________________
=========================================================================
From: "Ken Dangerfield" <bpyakd@mail.island.net>
Subject: Re: Capacitor sorce
Date: Mon, 1 Dec 1997 16:15:42 -0800
Source: Sound Digest Archive v01.n123
Phone Michael Percy for his catalogue. Lots of caps listed.
Michael Percy Audio Products
(415)669-7181
Fax (415)669-7558
Regards,
Ken Dangerfield
On 1 Dec 97 Edgar Faulkner said:
> I need a sorce for various caps, Cerifine and Hoveland mostly. My bookmark
> to the "The long awaited resource directory!" ain't connecting.
>
> ______________________________
> Ed Faulkner \ through a child's eyes
> Instructional Support Services \ sky is blue
> Washington State University \ grass is green
> Pullman, WA 99164 \ I want to see again
> (509) 335-7566 \
> efaulkne@wsu.edu. \_________________________________
>
>
>
=========================================================================
From: Ron Steinberg <ca789@freenet.toronto.on.ca>
Subject: Re: Capacitor sorce
Date: Mon, 1 Dec 1997 19:13:10 -0500 (EST)
Source: Sound Digest Archive v01.n123
Try The Parts Connection, www://wwwsonicfrontiers.com/tpc or
1-800-769-0747 or 905-829-5858.
Ron
On Mon, 1 Dec 1997, Edgar Faulkner wrote:
> I need a sorce for various caps, Cerifine and Hoveland mostly. My bookmark
> to the "The long awaited resource directory!" ain't connecting.
>
> ______________________________
> Ed Faulkner \ through a child's eyes
> Instructional Support Services \ sky is blue
> Washington State University \ grass is green
> Pullman, WA 99164 \ I want to see again
> (509) 335-7566 \
> efaulkne@wsu.edu. \_________________________________
>
>
======================================================================
Ron Steinberg Photographer <ca789@torfree.net>
Though self employed, my opinions do not reflect those of my employer.
======================================================================
=========================================================================
From: RALPH POWER <POWER.RALPH@epamail.epa.gov>
Subject: Capacitor sorce -Reply
Date: Tue, 02 Dec 1997 09:02:33 -0500
Source: Sound Digest Archive v01.n123
Hi Ed,
Then, of course, there is Tony at Handmade Electronics as a source for Hovlands,
Cerafines and most other tube amp parts.
He's at : http://pw2.netcom.com/~handmade/first.html
A great guy, good prices and selection, and fast service. Nice online catalog.
I use him alot of the time for my stuff mainly cause he's closest to me.
Then there is Welborne Labs, which is closer to you, in Colorado. Ron is also
a great guy and has all that stuff at good prices also. Online catalog in process.
He's at : http://www.welbornelabs.com/
FYI,
- Ralph
=========================================================================
From: Edgar Faulkner <efaulkne@wsunix.wsu.edu>
Subject: Re: Capacitor sorce -Reply
Date: Wed, 3 Dec 1997 09:18:11 -0800 (PST)
Source: Sound Digest Archive v01.n124
FYI, Welborn labs has cerifine caps on sale throught the end of the month.
Thanks to all who helped.
______________________________
Ed Faulkner \ through a child's eyes
Instructional Support Services \ sky is blue
Washington State University \ grass is green
Pullman, WA 99164 \ I want to see again
(509) 335-7566 \
efaulkne@wsu.edu. \_________________________________
=========================================================================
From: Steve Van Osdell <svanos@toast.net>
Subject: Capacitor voltages
Date: Mon, 26 Jan 1998 20:30:03 -0600
Source: Sound Digest Archive v01.n172
I think I have recently made a big mistake. I recapped a couple of amps
with caps that I don't think were rated high enough. They were 250 volts
but that was DC volts, I have learned. This is probably only 160 VAC. One
was a preamp and the other an amp. They have been working okay, but how
thin a line am I on? Should I be in a hurry to replace them? These were
low value (like .047, .022) Metallized Poly esters.
Any advice appreciated, Steve
=========================================================================
From: Simon Busbridge <S.C.Busbridge@bton.ac.uk>
Subject: Re: Capacitor voltages
Date: Tue, 27 Jan 1998 08:10:59 +0000 (GMT)
Source: Sound Digest Archive v01.n172
Steve,
It depends how you are using them. I would not exceed the 250 V DC
standing voltage across them - perferably keep a safe margin below this.
If you are using them across AC then with most capacitors the operating
voltage is downrated. About a year ago I foolishly used a 0.5 uF
capacitor rated at 3 kV DC across a full-wave rectified supply producing a
peak of 2.5 kV. I was really lucky because when this thing blew the
pressure inside pushed the inners across the lab with the force of a
cannon....be warned!!
Not wishing to further alarm you, but if a coupling capacitor does go
short it usually brings part of the HT onto the grid of the next stage.
This pushes the valve into overdrive. I've seen anodes glowing almost
white hot from this with the glass softening. If you are unsure about
the rating then it's best to play it safe.
Simon
Dr Simon Busbridge
Department of Mechanical and Manufacturing Engineering
University of Brighton
Lewes Road
Moulsecoomb
Brighton BN2 4GJ
UNITED KINGDOM
Tel: 0044 (0)1273 642542
Fax: 0044 (0)1273 642327
e-mail: s.c.busbridge@bton.ac.uk
"..biology is what you do when you don't have the maths for real
science.." (sliders)
On Mon, 26 Jan 1998, Steve Van Osdell wrote:
> I think I have recently made a big mistake. I recapped a couple of amps
> with caps that I don't think were rated high enough. They were 250 volts
> but that was DC volts, I have learned. This is probably only 160 VAC. One
> was a preamp and the other an amp. They have been working okay, but how
> thin a line am I on? Should I be in a hurry to replace them? These were
> low value (like .047, .022) Metallized Poly esters.
>
> Any advice appreciated, Steve
>
>
>
=========================================================================
From: Dale.Simon@ps.net
Subject: cap biasing
Date: Thu, 29 Jan 1998 16:48:00 -0600
Source: Sound Digest Archive v01.n175
Has anyone ever messed around with dc biasing polarized
capacitors?
Dale Simon
I couldn't stand it and broke down and ordered some back issues.
Oh I am weak.
=========================================================================
From: ROBERT ROSENTHAL <RBTR@mail.rkd.snds.com>
Subject: Cap combos
Date: Fri, 14 Nov 1997 11:32:21 -0600
Source: Sound Digest Archive v01.n109
Hey Joes-
Awhile back, I did alot of tweaking with different caps on
PP amps- I found that metallised of one dielectric between
preamp & driver, & foil of polyprop or 'styrene between
driver & output tubes worked best, along with all solens in
the ps.
Best regards, Rob
=========================================================================
From: Kalman Rubinson <rubinsnk@is2.nyu.edu>
Subject: Re: Cap Dielectric Absorption
Date: Thu, 5 Mar 1998 20:41:02 -0500 (EST)
Source: Sound Digest Archive v01.n209
On Fri, 6 Mar 1998, Ian McPhail wrote:
> Audio mag back in Feb, March 1980 had an excellent article on
> capacitor dielectric absorption by Walter Jung and Richard Marsh.
> They even had a circuit for measuring DA of various dielectrics.
> Checked our library and sure enough some lowdown bastard
> student had removed the article years back. If you can track it down
> the article is very informative.
It's available on the web at the Reliable Capacitor website along with
lots of other useful cap info.
Kal
=========================================================================
From: "Ian McPhail" <i.mcphail@rmit.EDU.AU>
Subject: Cap Dielectric Absorption
Date: Fri, 6 Mar 1998 11:38:19 +1100
Source: Sound Digest Archive v01.n209
Audio mag back in Feb, March 1980 had an excellent article on
capacitor dielectric absorption by Walter Jung and Richard Marsh.
They even had a circuit for measuring DA of various dielectrics.
Checked our library and sure enough some lowdown bastard
student had removed the article years back. If you can track it down
the article is very informative.
DA from poor to excellent went something like
electrolytic, polyester, polycarbonate, polypropylene, polystyrene,
teflon.
regards Ian
Ian McPhail i.mcphail@rmit.edu.au
RMIT Chem and Met Eng Dept 110
GPO Box 2476V
Melbourne 3001
Australia
tel +61 3 9660 2408
fax +61 3 9660 3746
=========================================================================
From: "Johannes S. Chiu" <jschiu@ctr.columbia.edu>
Subject: Cap Discussion on EWW
Date: Wed, 10 Jun 1998 14:35:30 -0400 (EDT)
Source: Sound Digest Archive v01.n308
Hi,
This may be old news to some people here, but I have just noticed that
there is a series of articles by Cyril Bateman on Electronic and
Wireless World on capacitors in this year's Feb., Apr.,May, and June
issue. Each articles limits itself to one or two types of caps, and
discusses construction and electrical properties, plus some measurement.
Just glancing through, I find this series more informative than the
Jung series in Audio Magazine. People interested should definetely
look it up.
The June artice discusses aluminum electrolytics and tantalum caps.
In particular, the author noticed that for wet type electrolytic caps,
esr depends heavily on temperature, with higher temp. showing lower
esr. So, maybe it would be good practice to place some types of ps caps closer
to your rectifier tubes. Also, caps heat up more if more current is passed
through. So, maybe the "dullness" in oil caps is not so much dependent
on small/large signal, but on how much it gets heated up from the signal?
- --
Johannes S. Chiu
jschiu@ctr.columbia.edu
Columbia University
New York City
=========================================================================
From: evaguido <EvaGuido@iaehv.nl>
Subject: Re: Cap Discussion on EWW
Date: Sun, 14 Jun 1998 01:07:46 +0200
Source: Sound Digest Archive v01.n310
At 14:35 10-6-98 -0400, Johannes S. Chiu wrote:
>
>Hi,
>
>This may be old news to some people here, but I have just noticed that
>there is a series of articles by Cyril Bateman on Electronic and
>Wireless World on capacitors in this year's Feb., Apr.,May, and June
>issue. Each articles limits itself to one or two types of caps, and
>discusses construction and electrical properties, plus some measurement.
>Just glancing through, I find this series more informative than the
>Jung series in Audio Magazine. People interested should definetely
>look it up.
Thanks for focussing us. I am following this articles for a while and find
them very fundamental
>The June artice discusses aluminum electrolytics and tantalum caps.
>In particular, the author noticed that for wet type electrolytic caps,
>esr depends heavily on temperature, with higher temp. showing lower
>esr.
That is true. I know this for a long time now (due to my EMC background)
and I think that is one of the reasons that souns changes with time
>So, maybe it would be good practice to place some types of ps caps closer
>to your rectifier tubes. Also, caps heat up more if more current is passed
>through.
Which exactly is the reason to take care to pass as little current as
possible ! Use high impedances !
>So, maybe the "dullness" in oil caps is not so much dependent
>on small/large signal, but on how much it gets heated up from the signal?
the current ...... another mistery explained
Have fun,
Guido
>--
>Johannes S. Chiu
>jschiu@ctr.columbia.edu
>Columbia University
>New York City
>
>
=========================================================================
From: Marc Stager <ssound@erols.com>
Subject: Cap options
Date: Wed, 11 Mar 1998 14:25:54 -0500
Source: Sound Digest Archive v01.n213
Looking for the best bang for the buck in a coupling and bypass cap:
These are some options: (PC = Parts Connection, MP = Michael Percy)
.01 uf/ 400 V 10% Polyester film ----------------- .18 -- Parts Express
.01 uf/ 600 V 2% PS film/foil, Rel-Cap RT ------- 2.95 -- PC, 1.95 MP
.01 uf/ 630 V 10% Wondercap "C" PS film/foil, ---- 2.50 -- MP
.01 uf/ 630 V 1% Wondercap "C" PS film/foil, ---- 3.00 -- MP
.01 uf/ 400 V 10% PS film/tinfoil Multicap RTX --- 3.57 -- PC, 2.95 MP
.01 uf/ 600 V 10% Metallized pp Multicap PPMFX --- 3.87 -- PC
.01 uf/ 600 V 10% Metallized pp Kimber Kap ------- 4.44 -- Kimber list price
.01 uf/ 600 V 10% PS film/tinfoil Multicap RTX --- 5.46 -- PC, 4.95 MP
.01 uf/ 600 V 10% PS film/foil SETI Infinicap ---- 6.50 -- PC
.01 uf/ 630 V 10% PS film/foil Signature Infinicap 8.50 -- MP
.01 uf/1600 V 5% PP film/foil Hovland MusiCap --- 9.70 -- PC
.01 uf/ 600 V 10% Teflon f/f Rel-Cap TFT -------- 28.00 -- PC
Seems like the Rel-Cap RT is the best deal in a boutique cap, but how much
worse will the 18 cent polyester be, particularly for a power supply bypass?
400 volts would be sufficient in all cases.
Percy offers the InfiniCaps in S or D type; S is euphonic midrange, D is
"pure straightwire bypass", offers 1% pair for ,50 additional per cap.
=========================================================================
From: Marc Stager <ssound@erols.com>
Subject: Re: Cap options
Date: Wed, 11 Mar 1998 15:24:43 -0500
Source: Sound Digest Archive v01.n213
At 06:49 PM 3/11/98 +0000, you wrote:
>> Looking for the best bang for the buck in a coupling and bypass cap:
>
>My take are 1000V 10% Foil & polypropylene Film Axial units from
>Arcotronics.
>
>These are sold as "industrial" types, are very nice and dirt-cheap.
>
>Later Thorsten
>>>>>>>>>>>>>>
Any idea who sells them in the USA?
____________________ MS
=========================================================================
From: Hugh Dean <aspen@alphalink.com.au>
Subject: Re: Cap options
Date: Thu, 12 Mar 1998 07:23:30 +1000
Source: Sound Digest Archive v01.n214
Marc Stager wrote:
> >> Looking for the best bang for the buck in a coupling and bypass cap:
> >
> >My take are 1000V 10% Foil & polypropylene Film Axial units from
> >Arcotronics.
I'd second that. When doing some listening tests with tubes I tried a
10uF 160V Arcotronics metallized polypropylene and it was almost as good
as some low value polystyrenes I tried.
The Italians make some wonderful caps. On the other hand, I cannot
recommend the German Wima MKP series; they do not sound so good.
Cheers,
Hugh R. Dean
Melbourne, Australia
=========================================================================
From: evaguido <EvaGuido@iaehv.nl>
Subject: Re: Cap options
Date: Thu, 12 Mar 1998 14:19:49 +0100
Source: Sound Digest Archive v01.n214
At 07:23 12-3-98 +1000, Hugh Dean wrote:
>Marc Stager wrote:
>
>> >> Looking for the best bang for the buck in a coupling and bypass cap:
>> >
>> >My take are 1000V 10% Foil & polypropylene Film Axial units from
>> >Arcotronics.
>
>
>I'd second that. When doing some listening tests with tubes I tried a
>10uF 160V Arcotronics metallized polypropylene and it was almost as good
>as some low value polystyrenes I tried.
>
>The Italians make some wonderful caps. On the other hand, I cannot
>recommend the German Wima MKP series; they do not sound so good.
Do you also mean the MKP10 series ? Sorry, but I still like them: high
value for money
Alternative is Solen or Chateauroux
Guido
>Cheers,
>
>Hugh R. Dean
>Melbourne, Australia
>
>
=========================================================================
From: "alfred trower" <sedht@hotmail.com>
Subject: Re: Re(2): Cap options
Date: Fri, 13 Mar 1998 08:40:12 PST
Source: Sound Digest Archive v01.n216
Thorsten wrote:
>RS Components.
>
>www.rs-components/rs/
>
>or so.
Yup, it's or so. A quick search found that it was
http://www.rs-components.com/rs
That's one ;-).
Two, is that they don't even have a distributor listed in the US.
Come on, guys, it just can't be that you cant get non botique brand 1%
PS caps in the US. Someone help us out here. I've tried all of the
usual suspects, and no dice.
Al
Alfred Trower
Consultant, Client/Server Systems
Supply Chain Specialist
- ----------------------------------
"The higher we soar the smaller we appear to
those who cannot fly." Friedrich Wilhelm Nietzsche
______________________________________________________
Get Your Private, Free Email at http://www.hotmail.com
=========================================================================
From: Torsten.Loesch@enhar-ha.nthames.nhs.uk
Subject: Re(2): Cap options
Date: Fri, 13 Mar 1998 14:28:32 +0000
Source: Sound Digest Archive v01.n216
Yo,
>
> Any idea who sells them in the USA?
>
RS Components.
www.rs-components/rs/
or so.
=========================================================================
From: Torsten.Loesch@enhar-ha.nthames.nhs.uk
Subject: Re(2): Re(2): Cap options
Date: Fri, 13 Mar 1998 16:19:22 +0000
Source: Sound Digest Archive v01.n216
Hi all,
> >RS Components.
> >
> >www.rs-components/rs/
> >
> >or so.
>
>
> Yup, it's or so. A quick search found that it was
>
> http://www.rs-components.com/rs
>
> That's one ;-).
Sorry, I'm on holiday. Just came into work for a few minutes. Forgot the
.com.
> Two, is that they don't even have a distributor listed in the US.
Funny, they show a presence in America on their map. Just e-mail them
someone.
> Come on, guys, it just can't be that you cant get non botique brand 1%
> PS caps in the US. Someone help us out here. I've tried all of the
> usual suspects, and no dice.
Sorry, I only know the UK where I pick them up in the shop down the road.
Later Thorsten
=========================================================================
From: Marc Stager <ssound@erols.com>
Subject: Cap options, corrected.
Date: Wed, 11 Mar 1998 14:32:52 -0500
Source: Sound Digest Archive v01.n213
Looking for the best bang for the buck in a coupling and bypass cap:
These are some options: (PC = Parts Connection, MP = Michael Percy)
.01 uf/ 400 V 10% Polyester film ----------------- .18 -- Parts Express
.01 uf/ 600 V 2% PS film/foil, Rel-Cap RT ------- 2.95 -- PC, 2.50 MP (5%)
.01 uf/ 630 V 10% Wondercap "C" PS film/foil, ---- 2.50 -- MP
.01 uf/ 630 V 1% Wondercap "C" PS film/foil, ---- 3.00 -- MP
.01 uf/ 400 V 10% PS film/tinfoil Multicap RTX --- 3.57 -- PC, 2.95 MP
.01 uf/ 600 V 10% Metallized pp Multicap PPMFX --- 3.87 -- PC
.01 uf/ 600 V 10% Metallized pp Kimber Kap ------- 4.44 -- Kimber list price
.01 uf/ 600 V 10% PS film/tinfoil Multicap RTX --- 5.46 -- PC, 4.95 MP
.01 uf/ 600 V 10% PS film/foil SETI Infinicap ---- 6.50 -- PC
.01 uf/ 630 V 10% PS film/foil Signature Infinicap 8.50 -- MP
.01 uf/1600 V 5% PP film/foil Hovland MusiCap --- 9.70 -- PC
.01 uf/ 600 V 10% Teflon f/f Rel-Cap TFT -------- 28.00 -- PC
Seems like the Rel-Cap RT is the best deal in a boutique cap, but how much
worse will the 18 cent polyester be, particularly for a power supply bypass?
400 volts would be sufficient in all cases.
Percy offers the InfiniCaps in S or D type; S is euphonic midrange, D is
"pure straightwire bypass". 1% pair cost .50 additional per cap.
_______________________________________________________ MS
=========================================================================
From: Marc Stager <ssound@erols.com>
Subject: Cap options, more
Date: Wed, 11 Mar 1998 15:28:44 -0500
Source: Sound Digest Archive v01.n213
Looking for the best bang for the buck in a coupling and bypass cap:
These are some options: (PC = Parts Connection, MP = Michael Percy)
.01 uf/ 400 V 10% Polyester film ----------------- .18 -- Parts Express
.01 uf/ 600 V 10% PP film Sprague 715P "Orange Drop" .78 -- Newark
.01 uf/ 600 V 10% PP film/foil Mallory PVC -------- 1.34 -- Newark
.01 uf/ 600 V 2% PS film/foil, Rel-Cap RT ------- 2.95 -- PC, 2.50 MP
.01 uf/ 630 V 10% Wondercap "C" PS film/foil, ---- 2.50 -- MP
.01 uf/ 630 V 1% Wondercap "C" PS film/foil, ---- 3.00 -- MP
.01 uf/ 400 V 10% PS film/tinfoil Multicap RTX --- 3.57 -- PC, 2.95 MP
.01 uf/ 600 V 10% Metallized pp Multicap PPMFX --- 3.87 -- PC
.01 uf/ 600 V 10% Metallized pp Kimber Kap ------- 4.44 -- Kimber list price
.01 uf/ 600 V 10% PS film/tinfoil Multicap RTX --- 5.46 -- PC, 4.95 MP
.01 uf/ 600 V 10% PS film/foil SETI Infinicap ---- 6.50 -- PC
.01 uf/ 630 V 10% PS film/foil Signature Infinicap 8.50 -- MP
.01 uf/ 1600 V 5% PP film/foil Hovland MusiCap --- 9.70 -- PC
.01 uf/ 600 V 10% Teflon f/f Rel-Cap TFT -------- 28.00 -- PC
Kal mentioned Newark - Looked up a few there. Confusion mounts.
Is the Orange Drop performance in the same class as the boutique types?
How about that Mallory PVC. Flame resistant, to boot, so if your equipment
is in a fire ...
Thorsten said "My take are 1000V 10% Foil & polypropylene Film Axial units
from Arcotronics. Where can they be found in the US?
(before)
Seems like the Rel-Cap RT is the best deal in a boutique cap, but how much
worse will the 18 cent polyester be, particularly for a power supply bypass?
400 volts would be sufficient in all cases.
Percy offers the InfiniCaps in S or D type; S is euphonic midrange, D is
"pure straightwire bypass". 1% pair are .50 additional per cap.
_________________________________________________ MS
=========================================================================
From: Rick Francis <rfranci@uoft03.UTOLEDO.EDU>
Subject: Cap or Choke-input filter w/ choke in ground leg?!?
Date: Thu, 25 Dec 1997 23:24:06 -0500 (EST)
Source: Sound Digest Archive v01.n146
I want to use a huge .475 ma 8H choke as PS filter for 845 amp but WV is
1.07 kw. Maybe I'll never get near that, but I'd like to leave lots of
room, might someday want to go over 1 KV etc. So where can I read up on
using filter chokes in the ground leg? Lotsa books say you can do it to
avoid exceeding insulating ratings, but I want to know if you add
inductances with input choke in pos leg, and if a choke in neg leg and
cap-input in pos leg = cap-input filter as if choke's not there, and if
there are different capacitance problems, and probably other things I
haven't thought of.
If someone can guide me to the books, I'd appreciate it.
Sorry if anyone believed me when I claimed I could get 10 vdc from 6.3
tranny by using its 107 ac primaries and a bridge. With the load of an 845
(3.75 A), I had to do a FW voltage doubler from ARRL with a couple big 6 A
diodes, 2 caps, the reg. 117 primaries, and about a .25 ohm resistor to
get 10.0 vdc under load. Works great now. Man I like how those big tubes
glow.
Rick Francis, rfranci@uoft03.utoledo.edu
=========================================================================
From: "Michael Cameron" <mncameron@worldnet.att.net>
Subject: cap orientation question
Date: Wed, 30 Dec 1998 07:32:47 -0800
Source: Sound Digest Archive v01.n552
Hello Joes
When using coupling caps like the audionote which have a marking for
orientation when installing in circuit, which way do you recommend? And to
add a little fuel to the question, why would it matter one way over the
other?
Thanks for your help
Michael
=========================================================================
From: Paul Joppa <pdj@ISDNseattle.net>
Subject: Re: cap orientation question
Date: Wed, 30 Dec 1998 18:42:11 -0800
Source: Sound Digest Archive v01.n553
Michael Cameron wrote:
>
> Hello Joes
>
> When using coupling caps like the audionote which have a marking for
> orientation when installing in circuit, which way do you recommend? And to
> add a little fuel to the question, why would it matter one way over the
> other?
I think the standard answer is that the outside foil should be
connected to the lowest impedance-to-ground point (driver plate not
output grid, ground not cathode, etc), to minimize the effect of
capacitive coupling to the largish surface area.
Anyone have better - or different - information?
- -Paul Joppa
=========================================================================
From: "PEARL Cust Serv" <custserv@pearl-hifi.com>
Subject: Re: cap orientation question
Date: Wed, 30 Dec 1998 22:09:49 -0700
Source: Sound Digest Archive v01.n553
As far as I know, Paul's answer is correct. Just remember that
circumstances can alter cases
Bill Perkins, PEARL Inc.
2528 19 St. S.W., Calgary, Ab.,
Canada T2T 4X3
Ph. 1 403 244 4434 Fx. 1 403 244 9026
- ----------
>From: Paul Joppa <pdj@ISDNseattle.net>
>To: Michael Cameron <mncameron@worldnet.att.net>
>Subject: Re: cap orientation question
>Date: Wed, Dec 30, 1998, 7:42 PM
>
>Michael Cameron wrote:
>>
>> Hello Joes
>>
>> When using coupling caps like the audionote which have a marking for
>> orientation when installing in circuit, which way do you recommend? And to
>> add a little fuel to the question, why would it matter one way over the
>> other?
>
>I think the standard answer is that the outside foil should be
>connected to the lowest impedance-to-ground point (driver plate not
>output grid, ground not cathode, etc), to minimize the effect of
>capacitive coupling to the largish surface area.
>
>Anyone have better - or different - information?
>
>-Paul Joppa
=========================================================================
From: evaguido <EvaGuido@iaehv.nl>
Subject: Re: cap orientation question
Date: Sat, 02 Jan 1999 20:18:59 +0100
Source: Sound Digest Archive v01.n554
At 07:32 30-12-98 -0800, Michael Cameron wrote:
>Hello Joes
>
>When using coupling caps like the audionote which have a marking for
>orientation when installing in circuit, which way do you recommend? And to
>add a little fuel to the question, why would it matter one way over the
>other?
I keep the "red" side of the AN paper in oils at the highest voltage
Sounded the best
Guido
>Thanks for your help
>
>Michael
>
>
>
=========================================================================
From: Thomas Danley <Tom@ppci.com>
Subject: Re: cap orientation question
Date: Thu, 31 Dec 1998 09:02:36 -0600
Source: Sound Digest Archive v01.n554
Paul Joppa wrote:
> Michael Cameron wrote:
> >
> > Hello Joes
> >
> > When using coupling caps like the audionote which have a marking for
> > orientation when installing in circuit, which way do you recommend? And to
> > add a little fuel to the question, why would it matter one way over the
> > other?
>
> I think the standard answer is that the outside foil should be
> connected to the lowest impedance-to-ground point (driver plate not
> output grid, ground not cathode, etc), to minimize the effect of
> capacitive coupling to the largish surface area.
>
> Anyone have better - or different - information?
>
> -Paul Joppa
Hi
Well if you can read this it means my e-mail server is back on line!!
Putting the "banded" end of the cap (outside foil) at the lower signal impedance
point is what was said in "the olden days" to be propper, for the reason you
mention.
It was thought to be a minor concern at audio frequencies but a definate "rule"
for RF and TV stuff.
Happy New years
=========================================================================
From: Douglas Purl <dcp@selway.umt.edu>
Subject: Re: cap orientation question
Date: Thu, 31 Dec 1998 17:36:21 -0700 (MST)
Source: Sound Digest Archive v01.n554
On Thu, 31 Dec 1998, Thomas Danley wrote:
> Putting the "banded" end of the cap (outside foil) at the lower signal
> impedance point is what was said in "the olden days" to be propper, for
> the reason you mention. It was thought to be a minor concern at audio
> frequencies but a definate "rule" for RF and TV stuff.
In the century preceding I worked for a coil and transformer manufacturer.
Spent a lot of time proofing prototypes in the Faraday cage, and building
test samples (the coil lineup for an aviation radio, e.g. -- fun). The
chief engineer wanted cap bands to ground side. I asked why. "Because
they will buy from someone else." I persisted. "Is there a scientific
reason?" I was always avid to learn the secrets of science and industry.
"Yes," he said, "very scientific. We like to make a profit. That means we
have to have customers."
BTW it was very quick and easy to rig up a circuit, in the days before PCB
became the rule. I punched a flat sheet of metal a foot long, bent an ear
on each end with a vise for feet, popped in the coils and cans, and put a
long terminal strip on each side. When I finished soldering p to p, I had
to draft a location schematic. Fortunately none of it took thought or
brains, so I was able to do the job.
Doug Purl
=========================================================================
From: "william gaw." <whg@tiac.net>
Subject: caps
Date: Mon, 16 Mar 1998 08:05:52 -0500
Source: Sound Digest Archive v01.n218
This is a multi-part message in MIME format.
- ------=_NextPart_000_002B_01BD50B2.56BBF040
Content-Type: text/plain;
charset="iso-8859-1"
Content-Transfer-Encoding: quoted-printable
Building a preamp with Allen Wright using his design for the balanced =
unit, and at the same time am building in fourth order active crossovers =
for my horns. What are people recommending now as least damaging to the =
sound for caps that aren't going to cost $20 a piece? I know this has =
been discussed within the apst couple of weeks, but I missed most of it =
due to time problems. Thanks. Bill Gaw
- ------=_NextPart_000_002B_01BD50B2.56BBF040
Content-Type: text/html;
charset="iso-8859-1"
Content-Transfer-Encoding: quoted-printable
<!DOCTYPE HTML PUBLIC "-//W3C//DTD W3 HTML//EN">
<HTML>
<HEAD>
<META content=3Dtext/html;charset=3Diso-8859-1 =
http-equiv=3DContent-Type>
<META content=3D'"MSHTML 4.71.1712.3"' name=3DGENERATOR>
</HEAD>
<BODY bgColor=3D#ffffff>
<DIV><FONT color=3D#000000 size=3D2>Building a preamp with Allen Wright =
using his=20
design for the balanced unit, and at the same time am building in fourth =
order=20
active crossovers for my horns. What are people recommending now as =
least=20
damaging to the sound for caps that aren't going to cost $20 a piece? I =
know=20
this has been discussed within the apst couple of weeks, but I missed =
most of it=20
due to time problems. Thanks. Bill Gaw</FONT></DIV></BODY></HTML>
- ------=_NextPart_000_002B_01BD50B2.56BBF040--
=========================================================================
From: Torsten.Loesch@enhar-ha.nthames.nhs.uk
Subject: Re: caps
Date: Tue, 17 Mar 1998 14:07:35 +0000
Source: Sound Digest Archive v01.n220
Hi,
> Building a preamp with Allen Wright using his design for the balanced unit,
> and at the same time am building in fourth order active crossovers for my
> horns. What are people recommending now as least damaging to the sound for
> caps that aren't going to cost $20 a piece? I know this has been discussed
> within the apst couple of weeks, but I missed most of it due to time
> problems. Thanks. Bill Gaw
Well, AW himself suggests the Kimber Units (formerly Sideral).
As long as 0.47uF are enough I suggest the Arcotronics Foil & Film series of
Capacitors (in 1000V) and the Arcotronics metalised Film with a Foil & Film
Bypass (0.01uF 1000V) for anything larger.
Both are available from RS and Farnell in the UK and someone just posted a US
source.
In case of metalised Cap's I tend to turn to Ansar Supersound Capacitors (400
and 630V) wich are jolly good but a bit hard to get outside Great Britain. If
you buy them in the UK, have a look at the Criclewood electronics
Advertisments in the HiFi-World DIY-Supplements.
Ansars are bypassed by me with Philips Tin/Lead Foil & Polystyrene Film
Cap's, 1n in 630V and where possible with a bit of consideration (I use 160V
rated units in situations where the constant DC-Voltage is substantially
below 160V but the B+ might be a bit higher like 195V) as 8.2nF 160V.
All these Cap's are high quality "industrial" Cap's and the cost is counted
in pennies and not pounds (the 4.7uF Ansar Supersound costs about 4 Pound and
the polystyrene bypass about 50 pence).
Later Thorsten.
=========================================================================
From: jc morrison <jcm@eclipse.net>
Subject: Re: Caps and detail, was Re: Any Ariel Builders?
Date: Tue, 02 Jun 1998 03:31:35 -0700
Source: Sound Digest Archive v01.n300
hey,
you forgot the room treatments...
tsk. tsk.
=========================================================================
From: "Doc B." <bottlehead@silverlink.net>
Subject: Caps and detail, was Re: Any Ariel Builders?
Date: Tue, 2 Jun 1998 09:10:27 -0700
Source: Sound Digest Archive v01.n300
>If I'm not mistaken, the Sideral Cap's are now called Kimber.
>
>I didn't like the Kimbers that much. Not much different from Solen /
>Ansar / ICW Capacitors.
That doesn't seem to be the same type of Siderials I've heard! I found them
much superior to Solens. I will say that those I've used are branded
Siderial. I don't know if they have since been taken over by Kimber, or if
they are indeed the same cap. I do know they have been very hard to get in
the past.
They seem to be the stuff of legend, some say thay are really just Rel-Caps,
or Hovlands with stranded leads, others say the guy who started the company
never filled orders ( hey sounds like me!), or that he went out of business.
I don't have anything firm to offer in the rumor dept., but the ones I have
used sounded very good.
>
>Of course, I'm listening to analog, so there as much detail as possible
>is liked. With a Seedee Player or X-Port Dac, the Deck is staked
>differently and you actually want to loose a lot of Information....
Oh yeah, well of course that must be where we digress. See, I'm known for
only CD and as little information as possible coming from my system. Those
record jackets covering the side wall of my listening room are empty, I use
them strictly to improve the side reflections.
In fact, lately I've been experimenting with leaving a CD in the transport
and uplugging everything in my system when I listen.
You wouldn't believe how low the noise floor is, and there is *absolutely*
no electronic sound in the presentation.
The other astounding thing is how incredibly close CD and LP sound when I
operate my system this way. In fact, it's almost impossible to distinguish
78s from XRCDs with your eyes closed.
Also, I am able to make a 50L6 sound virtually identical to a 10 with this
system (well, unless you drop them both on the floor - the mesh plate 10 was
somewhat more glassy sounding in this experiment, it gave a more delicate
presentation, but shattered a bit on transients)....I think this technique
may solve the DC vs. cap vs. IT problem altogether, one could just eliminate
all of them.
You see this all started a while back when the cat took one of my prized CDs
and chewed it badly. I put it back in the transport and it actually sounded
better!
At first I went for the obvious explanation - cat spit is the ultimate CD
treatment. After spending several thousand dollars on exhaustive research, I
found a company that said they would synthetically reproduce the formula,
but right as we were ready to unleash this product on the market, alas, they
were shut down by the ASPCA. Why I don't know.
I was pretty despondent at this point, when as often happens, I had an
epiphany - it wasn't the spit, it was the pits!
Obviously the cat had added pits to the CD when he chewed it.
There was the answer! By adding extra pits to the CD over the existing
information, we have added random information to the data stored on the
disc. Since the transport/DAC tends to eliminate these added "errors", we
are actually putting less information into the system. Voila, less
information, less "CD sound". In fact the player skipped over large areas of
detail. I realized that I was on to a new way to remove the extra detail...
Well, I decided to take this to the next level. I sanded the label side of
the CD right off with 50 grit.
Let me tell you folks, if you want CDs with an unbelievably low noise floor,
and no hint of "CD edge", this is the ultimate treatment, the ultimate
reduction of detail information. In fact, the CD sounded the same whether I
put it in the transport and hit play, or just left the transport turned off.
Absolutely no detail was present. And I knew I had solved the problem of
"too much detail" so prominent in modern hi-fi systems.
I decided to take this a bit further, and started pulling plugs on all my
other equipment. Wow! Virtually no detail, and lower noise floor to boot! It
just got better and better. Now CD sound was indistinguishable from LP
sound. Even my old Nakamichi 1000 with one of baby Katlyn's Barney tapes was
impossible to distinguish from my Linn/Koetsu Black playing my mint Living
Stereo Gaite Parisienne LP.
I heartily suggest this technique as the next wave in ultra-fi. There is no
listener fatigue, I seldom worry about whether I have the best components
anymore, and my wife is very happy that we no longer have big ugly speakers
in the living room ( I found out the system sounds just as good if they sit
out behind the blackberry patch in the back yard, and now the cat has a new
place to hide my CDs when he steals them - thanks Whizzer).
Forget hi-fi. Don't settle for the seductive qualities of lo-fi.
Try no-fi.
Doc B.
PS sorry Torsten, I just lose control sometimes. I'll take my medicine right
now.
=========================================================================
From: "Doc B." <bottlehead@silverlink.net>
Subject: Re: Caps and detail, was Re: Any Ariel Builders?
Date: Tue, 2 Jun 1998 10:47:27 -0700
Source: Sound Digest Archive v01.n300
Alas I'm afraid my American idioms have once again failed me.
I didn't mean to imply that my copy of Gaite Parisienne was in mint
condition, but rather that it is one of the rare pressings made on actual
peppermint candy. The presentation is very sweet, but a little hot.
Anybody else have one of these and know what it is worth?
Maybe even more than my original recipe Siderials, huh.
Doc B.
VALVE
coming soon - www.bottlehead.com
- -----Original Message-----
From: Le Cleac'h J.-M. <lecleach@cgi.ensmp.fr>
To: sound@deliverator.io.com <sound@deliverator.io.com>
Cc: Doc B. <bottlehead@silverlink.net>
Date: Tuesday, June 02, 1998 9:55 AM
Subject: Re: Caps and detail, was Re: Any Ariel Builders?
>> De : Doc B. <bottlehead@silverlink.net>
>> Date : mardi 2 juin 1998 18:10
>
>> Linn/Koetsu Black playing my mint Living Stereo Gaite Parisienne LP.
>
>That's the only case I know for which foreign tourists after a Parisian
>fiest stay "in mint condition".
>
>Best regards,
>
>Jean-Michel Le Cleac'h, Paris, France
>
>
>
=========================================================================
From: "Le Cleac'h J.-M." <lecleach@cgi.ensmp.fr>
Subject: Re: Caps and detail, was Re: Any Ariel Builders?
Date: Tue, 2 Jun 1998 18:50:10 +0200
Source: Sound Digest Archive v01.n300
> De : Doc B. <bottlehead@silverlink.net>
> Date : mardi 2 juin 1998 18:10
> Linn/Koetsu Black playing my mint Living Stereo Gaite Parisienne LP.
That's the only case I know for which foreign tourists after a Parisian
fiest stay "in mint condition".
Best regards,
Jean-Michel Le Cleac'h, Paris, France
=========================================================================
From: flegal@allaban.fr (Francois Yves Le Gal)
Subject: Re: Caps and detail, was Re: Any Ariel Builders?
Date: Tue, 02 Jun 1998 19:17:04 +0200
Source: Sound Digest Archive v01.n300
At 09:10 02/06/98 -0700, Doc B. wrote:
>They seem to be the stuff of legend, some say thay are really just Rel-Caps,
>or Hovlands with stranded leads, others say the guy who started the company
>never filled orders ( hey sounds like me!), or that he went out of business.
>I don't have anything firm to offer in the rumor dept., but the ones I have
>used sounded very good.
If I do remember correctly, Sidereal is a small Californian speaker
manufacturer who did design the caps for their own use. Being unable to
distrbute them, they struck a deal with Kimber, who resold them for quite a
while under the KimberKap brand. Now, Sidereal and Kimber seem to have
parted ways.
And yes, they do sound quite good...
François Yves Le Gal flegal@allaban.fr
Directeur Associé
Allaban WebSystems Tél : + 33(0)1 4756 0194
70, rue Rivay Fax : + 33 (0)1 4756 0305
F-92300 Levallois-Perret http://www.allaban.fr
=========================================================================
From: "blackie" <blackie@mail.infohouse.com>
Subject: Re: carbon comp resistors
Date: Wed, 25 Nov 1998 20:58:54 +0000
Source: Sound Digest Archive v01.n504
> Date: Wed, 25 Nov 1998 15:58:49 -0500
> From: RALPH POWER <POWER.RALPH@epamail.epa.gov>
> To: sound@deliverator.io.com
> Subject: 45 amp report - follow up
> I also changed the Radio Shack carbon films on the 5842 grid and cathode resistors
> with half watt carbon comps and immediately noticed more tonal color and less bite.
> I'm beginning to use more and more of them for what they can bring to the sound.
> The only place I've had a problem with them is using them as plate resistors in the 5687
> linestage. I had a pair make strange noises there, otherwise no problems and cheap
> too (Mouser, 28 cents each). Those were NOS carbon comp resistors.
>
> Is it generally not good to use carbon comps in plate circuits or did I just have some
> bad luck with the NOS ones? Can you use carbon comps in phono stages and
> other high gain circuits without noise problems ?
I am mighty familiar w/ carbon comps - they are the resistor of
choice for vintage guitar amp circuits. Indeed, they sound a shipload
better than metal films for plate loads. A lot less sterile, more
colorful. They are definitely noisier than metal films (haven't tried
carbon films). Guitar amps are pretty high gain, a typical
input is 100-200 millivolts. The noise manifests as hiss when
turned up quite loud with no input (well into distortion if
there were a typical input signal). Guitars are inherently noisy so
the resistor self-noise is drowned out as soon as input is applied.
Mouser has new manufacture Xicon 1/2 watts that are fine.
Old stock or well used carbon comps tend to make a crackling, frying
noise. Some have postulated that this is due to internal arcing
within the carbon resistive medium. They never make these weird
popping noises when they are new or in good condition...
blackie
blackie@tubesville.com
www.tubesville.com
=========================================================================
From: David Home <DHome@creo.com>
Subject: RE: Carbon Comps Was:45 amp report - follow up
Date: Wed, 25 Nov 1998 14:30:56 -0800
Source: Sound Digest Archive v01.n504
Ralph wrote:
s it generally not good to use carbon comps in plate
circuits or did I just have some
bad luck with the NOS ones? Can you use carbon comps in
phono stages and
other high gain circuits without noise problems ? I hope
so.
Contrary to the prevailing views, I used all CCs in my high
gain phono section, including plate load resistors and find that the CC
sound is just as welcome in this amp as it is any higher level amp. Having
left an all Holco preamp, I would never wish to go back. My old preamp had
that nagging " I think I'll watch some TV.." effect that is completely
missing with the new all CC design. Everyone writes, including the designer
of my phono section, noise this and detail that but I just don't hear it.
Their detail is my edginess I think.
Now really, what do I know? Did I build a COMPLETE phono
stage with all MF and another with all CC and do extensive listening tests?
Well...no but neither did they most likely. The noise/detail critisism just
keeps going around and around until it MUST be true! 8^) I think you either
like the CC/oiler sound or you don't. I sure do and it sounds like you do
too.
In my opinion, the only justifiable criticism of using CCs
on a MC phono amp is the sample to sample variation between resistors in
what needs to be a very accurate RIAA filter. That objection was addressed
soundly by Allen Wright in his SP #14 or #15 article on phono amps. He
pointed out that ALL DIY phono sections need to tweaked in because of
variations in capacitance due to cabling and layout. This is done by
altering both capacitor values AND resistor values within the filter, will
monitoring an injected square wave modified by a reverse RIAA filter. So
starting out with 1 or œ % components is a waste of time, unless you are
following the designer's layout and parts/cable chooses to the letter. And
were is the fun in that!
Regards, David
=========================================================================
From: el34@juno.com
Subject: Carbon resistors (info from MIT vol 17.)
Date: Thu, 25 Sep 1997 11:01:10 -0400
Source: Sound Digest Archive v01.n042
Here is some information on Carbon resistors that will help cut through
the BS that has been flying on this subject. This is OCR'd from the MIT
Radation Lab Series vol. 17_ Components Handbook_. I will put this up on
a web page along with the graphs as soon as I get a chance.
Composition resistors generate noise of two types. The first is the
thermal-agitation noise
which all resistive impedances generate, ordinarily called "Johnson
noise." The voltage
generated by a resistor into an open circuit is given by
E2 = 5.50 X 10-22TR Af.
(E squared = 5.5 x 10 to the minus 22nd xTR x delta F)
E = rms noise voltage.
T = temperature of resistor in degrees absolute.
R = resistance in ohms.
Af = bandwidth of noise-measuring instrument in cycles per second.
For instance, a 100,000-ohm resistor at 25'C, (298'K) generates 2.68 uv
of noise over a
bandwidth of 5 kc/sec. This type of noise is of great interest in
connection with radar-receiver
design, and is covered in detail in Vol. 18 of the Radiation Laboratory
Series.
The second type of noise is peculiar to composition resistors and
appears when direct current
flows through them. The noise voltage is a result of random changes in
IR-drop caused by random
changes in the resistance of the unit. The noisiness of a resistor can be
expressed in two ways:
rms microvolts per volt across the resistor, and relative resistance
change in rms parts per
million. These two expressions mean the same thing. The noisiness
depends, like Johnson noise,
on the width of the frequency band passed by the measuring instrument,
but in a different manner.
f2
E2 is proportional to log ----
f1
E = rms noise voltage.
f2 and f1, are upper and lower frequency limits of the
noise-measuring instrument.
This is the same as saying that for a constant bandwidth (for
example, 1 cps) the square of
the noise voltage is inversely proportional to the frequency.
The original workers in this field(1) determined this law to be true
up to 10 kc/sec and work done in the Radiation Laboratory has indicated
that it is probably still roughly true in the megacycle region. The noise
voltage is
nearly, but not exactly, proportional to the direct voltage across the
resistor, and for
resistors of the same inherent noisiness it is independent of the
resistance value. The longer a
resistor is, the less noisy it is, if all other factors are equal.
The composition-resistor specifications give as the upper limit of
permissible resistor
noisiness 3uv per volt for resistors of 1/2 watt or less, and 1.2uv per
volt for resistors of
more than 1/2 watt rating. The conditions under which the measurement is
to be made are described
in American War Standard C75.17-1944 entitled " Method of Noise-Testing
Fixed Composition
Resistors." These conditions are summarized as follows:
The direct voltage applied is the rated continuous-working voltage of
the
resistor, but never more than 300 volts. The noise-measuring
instrument
gives maximum response from 400 to 1000 cps, and is 3 db down at
about
70 and 5000 cps. The measurement is made by a substitution
procedure,
by seeing how much 1000-cps signal from a standard signal generator
is
required to make the noise meter read the same as it did with the
resistor
connected. Noise measurements are not required on resistors below
1000 ohms.
It is of interest to compare the amounts of the two kinds of noise
generated by a resistor
under various conditions. Figure 2-13 shows noise, in rms microvolts per
kilocycle per second,
as a function of frequency, for two values of resistance, without and
with direct voltage
applied. The horizontal lines show that Johnson noise is independent of
frequency. The sloping
lines are noise-voltage estimates for resistors that just meet the 1/2
watt specification
(3uv per volt) when measured with a noise meter of frequency limits from
70 to 5000 cps. lt will
be seen that at 1000 cps the carbon-noise voltage of a 100,000-ohm
resistor with 100 volts across
it is about 100 times as great as the Johnson-noise voltage and
completely covers it. At
frequencies higher than about 10 Mc/sec, however, the Johnson noise
becomes the more important
of the two. The same situation exists in a 1000-ohm resistor with 10
volts across it. For this
and other reasons carbon noise is of little interest in radar equipment
where high gain
amplifiers work well above 10 Mc/sec.
(1) C.J. Christensen and G. L. Pearson, "Spontaneous Fluctuations
in Carbon
Microphones and Other Granular Resistances," Bell Sys. Tech. J., 15,
197, (April 1936).
=========================================================================
From: rb8r@powermarketing.net
Subject: Card Processing
Date: Sat, 27 Dec 1997 09:43:10 -0600
Source: Sound Digest Archive v01.n146
Greetings,
I just visited your website and would like the opportunity to introduce my self. My name is Ron Kat
z. I am Vice President of Netcom Data Corp. We are a direct credit card processor for businesses
who accept Visa and MasterCard for payment from their customers.
If you accept these (and other major cards), I guarantee to reduce your fees (by eliminating the mid
dle-step and by connecting your business' monthly volume to that of other businesses). Funds contin
ue to be deposited electronically into your account at your bank.
Customer convenience continues to be the driving force behind the growth and success of credit card
acceptance at retail points of sale. We can offer you access to the fastest and most cost-effective
card clearing network in the country. It's called VISA-Net.
We offer the technology and advantageous pricing, superior even to that of the giant mega-processors
, but the personality of a fine boutique where you are an important and welcome customer.
We will need to speak so I can learn more about your volume and average ticket size before quoting f
ees -- but I can assure you that your experience with us will be very positive and the savings well
worthwhile.
Our services include:
· Low Discount rate for Visa and MasterCard acceptance.
· No per transaction fees, no daily batch fees, and no hidden fees.
· 24 hour toll free customer service.
· Check verification and ATM debit card acceptance.
If you would like to know more about our services, or do not currently accept credit cards and would
like to, please call us at (508) 466-7673.
Best Regards,
Ron Katz
RonK@powermarketing.net
Netcom Data Corp. is a registered Member Service Provider, VISA USA / MasterCard International, Memb
er Bank, Michigan National Bank, Detroit, MI.
=========================================================================
From: Dale.Simon@ps.net
Subject: Cary Audio
Date: Thu, 11 Jun 1998 12:02:00 -0500
Source: Sound Digest Archive v01.n308
Does anyone have any thoughts on the Audio Electronics kits?
Particularily the SE-1 300b kit and the SP-1A 15in/horn mid
speaker kit.
Thanks,
Dale
=========================================================================
From: "Andrej Detièek" <andrej.deticek@siol.net>
Subject: Re: Cary Audio
Date: Thu, 11 Jun 1998 21:23:39 +0200
Source: Sound Digest Archive v01.n308
Dale.Simon@ps.net wrote:
> Does anyone have any thoughts on the Audio Electronics kits?
> Particularily the SE-1 300b kit and the SP-1A 15in/horn mid
> speaker kit.
> Thanks,
>
> Dale
Hello,
I build an AES SE-1 300B kit some 4 years ago and have used it since.
The amp was a good deal, considering the price. Maybe today there is
more competition on the market and the decision would be more difficult.
The amp needs to be modified, in my opinion.
Three components which really made a *big* difference in sound, were in
my opinion the following:
1) Change of input tube from 6SL7 to 6SN7 tube( Of different brands). I
tried first different brands of 6SL7, including 6191 red RCA and, for
better in this place, a 6188 Sylvania, but a NOS 6SN7 tube really
brought the amp to *life* in every respect (Literally less distortion, a
lot more rhythm, transparency and frequency response - in bass and
highs). Obviously, the output tube's input capacitance needs a lower
impedance and higher current to be driven properly. The only penalty -
the amplification factor of 6SN7 tube is four times lower than the one
of the 6SL7. Most preamps should not really have a problem with this,
however...
2) I used as an output tube different brands of a 300B tube, but also
tried it with Sylvania VT-52 and and Chinese and RCA, GE 2A3 tubes. I
am afraid that the plate supply is a little on the high side for many of
the 2A3 tubes. The Chinese and RCA tubes I have certainly do not stand
it very well. This was one reason why I haven't used the amp with 2A3
tubes, the other being that I really do not have enough power for my
present resident speakers (Non- horns). I did try the amp with Edgar
horns at a friend of mine, so I know how it sounds on horns.
I tried the amp with VT-52 and enjoyed the sound tremendously, but
again, not enough power for my present speakers (I am soon going to
build Lowthers..)
3) Change the output tube grid capacitor. The original is a 0.22 uF
Kimber Cap. I know of worse caps, but there are a few better ones. A
Hovland music cap sounds quite a bit better to my ears. How about oils?
An Audio Note paper in oil aluminum foil sounds to me in this position
pretty bad, all muffled and distorting. A different story with their two
higher grades, the copper foil and silver foil. The AN Paper in oil with
copper foil sound just great: transparent, clean and relaxed. It is
still reasonably priced, in my opinion ( I know there are many who are
not willing to spend so much on a cap, but think of it like this: you
need only two, but what a difference in sound to the better!). The next
one, AN paper in oil with silver foil, costs a lot more, but the
difference in sound is not that much more as it was with the copper
type. However, some might find even this expensive cap justified (I used
a lower value, a 0.1 uF instead of 0.22 uF, because of the price!), as
the sound is even more refined, relaxed and less colored. Did try the
Vitamin Q caps. Not much to my tase, to muddy. Knowing some other
audiophile plastic caps from other amplifiers, I did not try them here,
because I felt they would not "fit" my taste here.
4) Change of two cheap standard PS rectifiers to HEXFREDs brought a
noticeable improvement, mostly less hash and grain.
5) Oh, yes I changed all the connectors to "audiophile" types - Cardas.
Can't say how much difference this makes, because I installed them from
the start.
I am sure there are several other possible improvements you could make
and can read about them elsewhere, which I haven't tried. I feel the
amp is a very good one, if you implement some modifications and
definitely worth the price of the kit and the few modifying components.
Without changing the input tube and the coupling cap, I would be less
enthusiastic about it.
I am aware of the existence of a Deluxe version of this amp kit, but not
having heard it, can't comment on it. Maybe somebody else would?
Andrej Deticek
=========================================================================
From: Roscoe Primrose <roscoe@aiko.com>
Subject: Re: Cary Audio
Date: Thu, 11 Jun 1998 23:13:33 -0400
Source: Sound Digest Archive v01.n309
Dale.Simon@ps.net wrote:
>
> Does anyone have any thoughts on the Audio Electronics kits?
> Particularily the SE-1 300b kit and the SP-1A 15in/horn mid
> speaker kit.
> Thanks,
>
> Dale
The SE-1 kit, which is available w/300Bs or 2A3s sounds much better
w/2A3s, and is actually quite good that way. Can't recommend the SP-1A
much...
Peace
- --
Roscoe Primrose
- -- mailto:roscoe@aiko.com -- http://www.aiko.com/roscoe --
"Once in a while you get shown the light
In the strangest of places if you look at it right." Robert Hunter
=========================================================================
From: evaguido <EvaGuido@iaehv.nl>
Subject: Re: Cary Audio
Date: Sun, 14 Jun 1998 01:07:49 +0200
Source: Sound Digest Archive v01.n310
Better take the Audio Note kit one, see also SP#6
Guido
At 12:02 11-6-98 -0500, Dale.Simon@ps.net wrote:
> Does anyone have any thoughts on the Audio Electronics kits?
> Particularily the SE-1 300b kit and the SP-1A 15in/horn mid
> speaker kit.
> Thanks,
>
> Dale
>
>
=========================================================================
From: Gary Johnston <garyj@superlink.net>
Subject: Cary Cad 300SE outputs?
Date: Fri, 12 Jun 1998 07:55:42 -0700
Source: Sound Digest Archive v01.n309
Anyone familiar with these output transformers? I was wondering if
anyone can tell me who makes these babies and their impedance. Inherited
a pair of these and was wondering about their quality, etc.
Thanks on advance.
Gary
=========================================================================
From: Grover Gardner <groverg@postoffice.att.net>
Subject: Re: Cascading transformers
Date: Fri, 30 Oct 1998 09:30:16 -0600
Source: Sound Digest Archive v01.n473
At 8:46 PM +1030 10/30/98, Sellek, Grant (TSA) wrote:
>Hi All,
>
>I've been scrounging the local electronics stores for 2.5V AC transformers
>to power a heatament, sorry, filler. Can't find any.
>
>So Atomic Brain thinks, "why not put two of those widely available 240V:24V
>trannies (240V mains here) in series? Should be 2.4V AC output."
>
>What's the catch? I only want 5VA, so would a pair of 5VA trannies be OK?
>
>Or would it be smarter, and cheaper, to get one 6V tranny and put a resistor
>in series with the filament to drop it to 2.5V?
How about *half* a 6.3vct tranny (i.e. 3.15v)? The drop from 6.3 to 2.5
will need some mighty big dropping resistors and will throw off a lot of
heat...
Grover Gardner
groverg@postoffice.att.net
=========================================================================
From: Simon Busbridge <S.C.Busbridge@bton.ac.uk>
Subject: Re: Cascading transformers
Date: Fri, 30 Oct 1998 10:45:28 +0000 (GMT)
Source: Sound Digest Archive v01.n473
Hi Grant
Interesting idea. It will be interesting to hear what others have to
say, but my initial reaction is that the second transformer will be
working very inefficiently because the flux level in its core will be very
low. Basically there will be too many turns on the primary (and hence on
the secondary also) for the operating voltage so you might find that the
resisance of the windings has a dominant effect on the regulation.
Best wishes
Simon
Dr Simon Busbridge
School of Engineering
University of Brighton
Lewes Road
Moulsecoomb
Brighton BN2 4GJ
UNITED KINGDOM
Tel: 0044 (0)1273 642542
Fax: 0044 (0)1273 642327/642301
e-mail: s.c.busbridge@bton.ac.uk, scbusbridge@hotmail.com
On Fri, 30 Oct 1998, Sellek, Grant (TSA) wrote:
> Hi All,
>
> I've been scrounging the local electronics stores for 2.5V AC transformers
> to power a heatament, sorry, filler. Can't find any.
>
> So Atomic Brain thinks, "why not put two of those widely available 240V:24V
> trannies (240V mains here) in series? Should be 2.4V AC output."
>
> What's the catch? I only want 5VA, so would a pair of 5VA trannies be OK?
>
> Or would it be smarter, and cheaper, to get one 6V tranny and put a resistor
> in series with the filament to drop it to 2.5V?
>
> Thanks,
> Grant
>
>
> Grant Sellek
> Adelaide, Australia
> grant.sellek@roads.sa.gov.au
>
>
=========================================================================
From: "Sellek, Grant (TSA)" <Grant.Sellek@roads.sa.gov.au>
Subject: Cascading transformers
Date: Fri, 30 Oct 1998 20:46:58 +1030
Source: Sound Digest Archive v01.n473
Hi All,
I've been scrounging the local electronics stores for 2.5V AC transformers
to power a heatament, sorry, filler. Can't find any.
So Atomic Brain thinks, "why not put two of those widely available 240V:24V
trannies (240V mains here) in series? Should be 2.4V AC output."
What's the catch? I only want 5VA, so would a pair of 5VA trannies be OK?
Or would it be smarter, and cheaper, to get one 6V tranny and put a resistor
in series with the filament to drop it to 2.5V?
Thanks,
Grant
Grant Sellek
Adelaide, Australia
grant.sellek@roads.sa.gov.au
=========================================================================
From: Paul Joppa <pdj@ISDNseattle.net>
Subject: Re: Cascading transformers
Date: Fri, 30 Oct 1998 09:17:14 -0800
Source: Sound Digest Archive v01.n474
Sellek, Grant (TSA) wrote:
> ...snip...
> So Atomic Brain thinks, "why not put two of those widely available 240V:24V
> trannies (240V mains here) in series? Should be 2.4V AC output."
>
> What's the catch? I only want 5VA, so would a pair of 5VA trannies be OK?
...snip...
Good news: You can ground the intermediate windings to obtain some
filament isolation.
Bad news: The second (24:2.4v) transformer will have too much winding
resistance by a factor of 10 - it's designed for 1/10 the current. A
50VA unit would be just right...
- -Paul Joppa
=========================================================================
From: evaguido <EvaGuido@iaehv.nl>
Subject: Re: Cascading transformers
Date: Sun, 01 Nov 1998 13:18:27 +0100
Source: Sound Digest Archive v01.n476
At 20:46 30-10-98 +1030, Sellek, Grant (TSA) wrote:
>Hi All,
>
>I've been scrounging the local electronics stores for 2.5V AC transformers
>to power a heatament, sorry, filler. Can't find any.
>
>So Atomic Brain thinks, "why not put two of those widely available 240V:24V
>trannies (240V mains here) in series? Should be 2.4V AC output."
>
>What's the catch?
Expensive and bigger.........
I only want 5VA, so would a pair of 5VA trannies be OK?
>
>Or would it be smarter, and cheaper, to get one 6V tranny and put a resistor
>in series with the filament to drop it to 2.5V?
lots of heat.....?
Try to find E-I core transformers that you can de-wind (=release windings
untill desired voltage is there)
Otherwise two equal (and equally loaded) 5 V trannies with their primaries
in series will work as well
Succes
Guido
>Thanks,
>Grant
>
>
>Grant Sellek
>Adelaide, Australia
>grant.sellek@roads.sa.gov.au
>
>
=========================================================================
From: evaguido <EvaGuido@iaehv.nl>
Subject: Re: Cascading transformers
Date: Sun, 01 Nov 1998 14:12:50 +0100
Source: Sound Digest Archive v01.n476
At 09:17 30-10-98 -0800, Paul Joppa wrote:
>Sellek, Grant (TSA) wrote:
>> ...snip...
>> So Atomic Brain thinks, "why not put two of those widely available 240V:24V
>> trannies (240V mains here) in series? Should be 2.4V AC output."
>>
>> What's the catch? I only want 5VA, so would a pair of 5VA trannies be OK?
>...snip...
>
>Good news: You can ground the intermediate windings to obtain some
>filament isolation.
Bingo !
But you can "ground" every seconary winding, that is why I alsways use
small caps from any heater to ground (or cathode, in the IHT)
>Bad news: The second (24:2.4v) transformer will have too much winding
>resistance by a factor of 10 - it's designed for 1/10 the current. A
>50VA unit would be just right...
Yes, the 2 trannie sollutions is not very efficient.......
Guido
>-Paul Joppa
>
>
=========================================================================
From: Paul Joppa <pdj@ISDNseattle.net>
Subject: Re: Cascading transformers
Date: Sun, 01 Nov 1998 18:08:20 -0800
Source: Sound Digest Archive v01.n477
evaguido wrote:
> >... You can ground the intermediate windings to obtain some
> >filament isolation.
>
> Bingo !
>
> But you can "ground" every seconary winding, that is why I alsways use
> small caps from any heater to ground (or cathode, in the IHT)
Sorry, I was not very clear. I was referring to electrostatic
isolation from power-line nasties. Best of course is to use a shielded
secondary with the shield grounded (as mentioned by Lynn a few weeks
ago) but often power transformers are wound without interleaving so
one winding can act as a "shield" for another.
- -Paul Joppa
=========================================================================
From: peterca@ento.csiro.au
Subject: Re: Cascading transformers
Date: Mon, 2 Nov 1998 15:11:04 +1100 (EST)
Source: Sound Digest Archive v01.n477
Hello Grant,
>I've been scrounging the local electronics stores for 2.5V AC transformers
>to power a heatament, sorry, filler. Can't find any.
>....I only want 5VA.......
You want 2 amps at 2.5V?
>Or would it be smarter, and cheaper, to get one 6V tranny and put a resistor
>in series with the filament to drop it to 2.5V?
I think Jaycar, DS etc. stock a cheapish tranny which has multiple taps and
is rated for 2A on the secondary (regardless of which taps are chosen). I
think it has taps for 12V, 15V, 18V etc. The difference there is 3V.
Dropping 3V to 2.5V at 2 amps requires a 1ohm resistor to dissipate only 1
watt. That should be just enough to slow the in rush current a bit without
being too much of a fiddle to get the value just right.
Dr. Peter Campbell (Peter.Campbell@ento.csiro.au)
Div. Entomology, C.S.I.R.O. Ph.61-2-62464053 or -62464158 (w)
Box 1700 Canberra A.C.T. 2601 61-2-62516213 (h)
Australia 61-2-62464173 (fax)
=========================================================================
From: evaguido <EvaGuido@iaehv.nl>
Subject: Re: Cascading transformers
Date: Mon, 02 Nov 1998 22:20:42 +0100
Source: Sound Digest Archive v01.n478
At 18:08 1-11-98 -0800, Paul Joppa wrote:
>evaguido wrote:
>> >... You can ground the intermediate windings to obtain some
>> >filament isolation.
>>
>> Bingo !
>>
>> But you can "ground" every seconary winding, that is why I alsways use
>> small caps from any heater to ground (or cathode, in the IHT)
>
>Sorry, I was not very clear. I was referring to electrostatic
>isolation from power-line nasties. Best of course is to use a shielded
>secondary with the shield grounded (as mentioned by Lynn a few weeks
>ago) but often power transformers are wound without interleaving so
>one winding can act as a "shield" for another.
OK, true and use short wire to connect the shield to the system reference
(not always ground, but often the conducting cabinet). If your transformer
does not have a shield you can use capacitors from all the secondaries and
connect those to the reference
Guido
>-Paul Joppa
>
>
=========================================================================
From: Rick Francis <rfranci@uoft03.UTOLEDO.EDU>
Subject: RE: CAT5 as Speaker cable
Date: Fri, 10 Oct 1997 16:11:43 -0400 (EDT)
Source: Sound Digest Archive v01.n063
On Fri, 10 Oct 1997, Markowitz, Gary wrote:
> I've gotten the stuff for free from the network guys at work (they've
> always got a couple of remnant rolls with about 100 feet or so lying
> around), and if you work at a place where they've got a sizeable
> computer department, ask around and you'll probably be rewarded too.
>
I found a bunch of this being tossed after some wiring job here on
campus. I think it's 24 ga. solid, twisted pair, 2 pairs per run in blue
insulation. I use it as speaker cable all sorts of places. Haven't
compared to other stuff but seems to work fine.
Rick
=========================================================================
From: Stewart Ferrell <sferrell@pfmc.net>
Subject: Re: CAT5 as Speaker cable
Date: Sat, 11 Oct 1997 16:18:06 -0400
Source: Sound Digest Archive v01.n065
Rick Francis wrote:
> On Fri, 10 Oct 1997, Markowitz, Gary wrote:
>
> > I've gotten the stuff for free from the network guys at work
> (they've
> > always got a couple of remnant rolls with about 100 feet or so lying
>
> > around), and if you work at a place where they've got a sizeable
> > computer department, ask around and you'll probably be rewarded too.
>
> >
> I found a bunch of this being tossed after some wiring job here on
> campus. I think it's 24 ga. solid, twisted pair, 2 pairs per run in
> blue
> insulation. I use it as speaker cable all sorts of places. Haven't
> compared to other stuff but seems to work fine.
>
> Rick
As a computer person I know that this wire is also OFC!
Stewart
=========================================================================
From: Josh Karnes <karnes@usa.net>
Subject: CAT-5 cable is good
Date: Fri, 24 Oct 1997 09:45:25 -0500
Source: Sound Digest Archive v01.n084
recently gary m. posted regarding the use of plenum-type CAT-5 wire pairs
for interconnects with success. i have to second that!
i built a two pair of interconnects last night for my system out of LAN-TEK
plenum cat-5 wire pairs (taken from a cat-5 cable, they contian 4 pair).
these are the same type (although not the same brand name) as gary m. used,
they have teflon insulation and are OFC 22 awg solid wire with about two
twists per inch. i made 6 foot interconnects to connect my cd player and
my surround sound processor to my amplifier. in fact i used the cheap PVC
insulated nickel RCA connectors from radio shack (as a stop gap until i
select another kind of connector to use). the cables i was replacing are
the regular radio-shack gold-plated $15 1-meter jobbies.
the improvement in sound quality was definitely noticeable (although my
wife said i was "definitely smoking dope" if i thought there was any
difference between cables). better soundstage, more "air" around the
instruments. noticed it bigtime on the cowboy junkies' trinity session. i
like them! and cheap too! as soon as i can find a connector which will
connect up to my grace tonearm i'll build a set for the phono.
later-
- -- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
josh_karnes:
shileen's husband, jordan and hannah's daddy, guitarist, drummer,
composer, songwriter, audiophile, computer geek, mechanic, carpenter,
wannabe gourmet chef, keeper of the faith <><
=========================================================================
From: Scott Grammer <gesic@cdc.net>
Subject: Re: CAT-5 cable is good
Date: Fri, 24 Oct 1997 12:45:25 -0400
Source: Sound Digest Archive v01.n084
Josh:
While I'll try not to make the connection between unshielded
interconnects and the fact that you have a hum problem (whoops, did it
any way. Oh, well...) I will suggest that you put the end of those
twisted pairs in a drill and twist them to about 6-8 turns per inch.
Cheers!
S.G.
- --
"To save every cog and wheel is the first
precaution of intelligent tinkering." -Aldo Leopold.
Check out TubeDude's Webpage of Vacuum Tube Lore!
http://www.cdc.net/~gesic
=========================================================================
From: "Bottlehead" <Bottlehead@prodigy.net>
Subject: Re: CAT5 speaker cable?
Date: Mon, 16 Feb 1998 14:19:58 -0800
Source: Sound Digest Archive v01.n194
> Second, i'm thinking of using it for internal wire for speakers (i'm
going
> to build a pair of Superwhamos). Anyone compared it to Bottlehead's
> recommended 12ga house wire in this configuration?
The 12 ga. is long since gone, except I guess there's still some hooked to
the subs (about 4 inches).
I had good luck with 18 ga. solid on the mids and 22 ga. solid on the
highs. If you're really macho, strip the insulation off and run the wire
butt nekked. I bet a Solo inductor, unwound and wrapped with teflon
plumbing tape would make good internal wire too.
Next sperment will be Jena 18 ga. Hookup, mighty nice stuff, but $$$ for
all the wire you need to hook all them mids together.
(speaking of
> Superwhamos, has anyone tried vintage oil caps for the crossover? I have
> a bunch of 200v 1% Southeastern and CDE caps to try)
Yeah, they work great. I used two 3 mfd GE motor start caps in parallel on
the tweet, and that setup whupped both a 6 mfd ($$!) Hovland and a 6.8 mfd
Black Gate soundly.
By the way, don't build the Supers, build the Hypers, with the tapered pipe
enclosure. Coat the mids and tweets with Ennemoser Lack, line the cabinets
with felt, stuff the pipes lightly (maybe 1/4 lb.) with real wool. Stuff
the back chamber of the sub with 1 lb. fiberfill. Use a thick (1-1/2")
front baffle, and round the edges, maybe 1-1/2" radius if possible. Open up
the tweet and put a 3/8" dot of felt on the pole piece, and put a small
square of foam on top of it. Use Andy Bartha's small Whatchamacallits
between the tower and the sub.
Try about 10W SE.
Doc B.
=========================================================================
From: Dave Stagner <dstagner@icarus.net>
Subject: CAT5 speaker cable?
Date: Mon, 16 Feb 1998 15:11:19 -0600 (CST)
Source: Sound Digest Archive v01.n194
I know some of you have tried CAT5 network cable as speaker cable. Any
comments on how it works, or suggestions on how to use it?
I have two general questions in mind... first, to banana or not to banana.
Since it's solid core, i could easily just strip it and use the bare ends
with the binding posts. Is there any advantage to actually putting a
connector on the end?
Second, i'm thinking of using it for internal wire for speakers (i'm going
to build a pair of Superwhamos). Anyone compared it to Bottlehead's
recommended 12ga house wire in this configuration? (speaking of
Superwhamos, has anyone tried vintage oil caps for the crossover? I have
a bunch of 200v 1% Southeastern and CDE caps to try)
I hope it works out... it seems like a cheap way to bi-wire.
- -dave
Practice beautiful randomness and act kind of senseless.
<dstagner@icarus.net>
=========================================================================
From: STEVE CORNETT <SCORNETT@usagroup.com>
Subject: CAT5 speaker cable?
Date: Tue, 17 Feb 1998 07:43:41 -0600
Source: Sound Digest Archive v01.n194
Dave asked:
"...to banana or not to banana. Since it's solid core, i could easily just
strip it and use the bare ends with the binding posts. Is there any
advantage to actually putting a connector on the end?"
Personally, I always use solid core wire with bare ends. There's no
connector like no connector. Can't speak to the CAT5 in particular,
though.
Steve C.
"The earth is just to too small and
fragile a basket for the human race
to keep all its eggs in." - Heinlein
=========================================================================
From: Torsten.Loesch@FinanceManager.Finance.FinanceAndInformation.enhar-ha.nthames.nhs.uk
Subject: Re: CAT5 speaker cable?
Date: Tue, 17 Feb 1998 09:08:10 +0000
Source: Sound Digest Archive v01.n194
Yo 'dettes 'n dudes
> I know some of you have tried CAT5 network cable as speaker cable. Any
> comments on how it works, or suggestions on how to use it?
It's good, but not good enough.
I used it in two runs with all cores in each run paralleled. That gives you
13Gauge Copper Equivalent in a construction a lot like Kimber which seems
okay in rejecting RF. Capacitance is low (important for Valve Amp's) and the
Inductance is very moderate too. But there is better out there.
> I have two general questions in mind... first, to banana or not to banana.
Don't. I use the (316-A code) spades from Radioshack/Tandy. These are copper
(good) under Goldplating (Yuck - not the Gold, but the Junk needed to make
the Gold stick to the Copper) and if you crimp them REALLY HARD you'll get
a nice "coldweld".
> Since it's solid core, i could easily just strip it and use the bare ends
> with the binding posts. Is there any advantage to actually putting a
> connector on the end?
Yes. Copper oxidises. Copper Oxid makes briliant rectifiers.
As for a realy good Speaker Cable in DIY, the stuff I'm using now is a bit
more expensive to make (USD 3-4 per meter) and also a bit more difficult,
but I think it pretty much equals all these Foil Tapes and similar stuff
while it has mucho better electrical properties (about 50puffs/foot and
still very low inductance).
A detailed Article on the whole subject will appear soon on TNT-Audio. At
the moment I'm "field-testing" the Cable, if anyone wants to participate
please e-mail me directly and I send you the Instructions on how to make
the Cable.
Later Thorsten
=========================================================================
From: Peter Sikking <peter.sikking@amc.de>
Subject: Re: CAT5 speaker cable?
Date: Tue, 17 Feb 1998 12:44:55 +0000
Source: Sound Digest Archive v01.n194
Steve wrote:
> > "...to banana or not to banana.
> Personally, I always use solid core wire with bare ends. There's no
> connector like no connector.
Renember that you only have no conector when you solder you cable
directly to the OPT or speaker(chassis) terminals.
For an alternative for `audiophile' binding posts and bananas, look
in your electronic parts catalogs for lab connnectors (those things on
your multimeter). If you are lucky you will find very nice gold (OK) or
silver (YES!) plated 4mm bananas and sockets, all rated for 10 Amps.
I especially like the ones made of thin sheet instead of with solid
pongs.
--Peter
music lover, ultra-fi builder, GUI designer & developer, on drums...
from:amsterdam@ulm.germany +49 731 505 1679 facsimile +49 731 505 1808
=========================================================================
From: Conrad Drake <conrad.drake@intellect.com.au>
Subject: Re: CAT5 speaker cable?
Date: Wed, 18 Feb 1998 10:55:54 +0800
Source: Sound Digest Archive v01.n195
>>>
<Torsten.Loesch@FinanceManager.Finance.FinanceAndInformation.enhar-ha.nthames.nhs.uk>
02/17 5:08 pm
> I use the (316-A code) spades from Radioshack/Tandy. These are copper
>(good) under Goldplating (Yuck - not the Gold, but the Junk needed to make
>the Gold stick to the Copper) and if you crimp them REALLY HARD you'll get
>a nice "coldweld".
Umm, could you please elaborate? I'm about half way through changing from
conventional (ie tinned) to gold-pated RCA line connectors as I had had
enough
corrosion to audilbely ugly-up the sound (sort of harsh, thin sound at low
levels - bit like an old
TV B class output stage). First "cable nonsense" I've actually heard
Are there "good" and "bad" methods of gold plating? And how do you tell
them apart?
Likewise I've changed the speaker connectors (on 1mm solid copper
@ 10mm seperation, untwisted - local 15A household mains cable ) to
either solder joints or screw-down gold contacts.
>> Since it's solid core, i could easily just strip it and use the bare ends
>> with the binding posts. Is there any advantage to actually putting a
>> connector on the end?
>
>Yes. Copper oxidises. Copper Oxide makes briliant rectifiers.
So, if I understand correctly, you would recommend hi-contact pressure
between "tin plate"/"tin plate" not copper/gold-plate or gold/gold?
Or am I getting my lines crossed again?
Conrad Drake
=========================================================================
From: Torsten.Loesch@FinanceManager.Finance.FinanceAndInformation.enhar-ha.nthames.nhs.uk
Subject: Re(2): CAT5 speaker cable?
Date: Fri, 20 Feb 1998 07:10:53 +0000
Source: Sound Digest Archive v01.n197
Yo,
> Umm, could you please elaborate? I'm about half way through changing from
> conventional (ie tinned) to gold-pated RCA line connectors as I had had
> enough corrosion to audilbely ugly-up the sound (sort of harsh, thin sound
> at low levels - bit like an old TV B class output stage).
Well, goldplating is electroplating. Silver will nicely stick to everything,
so silverplated Plugs would be better (the Neutrik XLR's use generally
silver-
plated connector parts). Even better would be solid silver RCA's (Audio Note
sells these - mega $$$$).
The Gold usualy needs another metal below it to stick well. I'm not quite
sure what is used (probably nickel - use a nice Iron-plug then and save the
hassle of using Brass or Copper plugs....) but it certainly does not improve
the sound. Solid gold connetors (say six 9) would be another story of course.
That said, I still use goldplated stuff as I cannot find anything nice
silverplated.
> Are there "good" and "bad" methods of gold plating? And how do you tell
> them apart?
Dunno.
> Likewise I've changed the speaker connectors (on 1mm solid copper
> @ 10mm seperation, untwisted - local 15A household mains cable ) to
> either solder joints or screw-down gold contacts.
Not such a bad Idea. I personally want to retain the flexibility though.....
> So, if I understand correctly, you would recommend hi-contact pressure
> between "tin plate"/"tin plate" not copper/gold-plate or gold/gold?
No plating is best. Best is either solid silver or copper, coldwelded
to the same Metal. Thus we need strong solid silver binding posts and
silver cable (onobtanium for all it's worth) or pure copper binding
posts (some are made but have problems with mechnical integrity) and
pure copper Cable. In either case the contact area must be of a type
that can either:
completly evacuate and seal the joints
or achieve a "coldweld" by fusing the cables metal to the posts metal.
Non of that is very practical, so we are stuck with goldplated brass
in most cases.
Later Thorsten
=========================================================================
From: "Aaron Bohnen" <bohnen@mail.unixg.ubc.ca>
Subject: Re: CAT5 speaker cable? & connectors
Date: Fri, 20 Feb 1998 11:27:50 +0000
Source: Sound Digest Archive v01.n197
Hi Dave,
About RCA connectors to fit smaller jacks:
> Speaking of RCA connectors, does anyone know of a high-quality, affordable
> RCA plug that is small enough to fit the close-spaced jacks of vintage
> tube gear? All those Cardas and other plugs designed to work with
> undersea-sized cables just don't fit, leading to poor connections.
I'd have a good look at the Canare F-09 and F-10 RCA connectors. They
are good quality and more suitable in size and shape for vintage
equipment than most of the snooty audiophile brands. Good quality as
well - brass bodies with gold plated contacts, teflon insulation, etc.
Another good idea is to replace those nasty old corroded crappola jacks
in your equipment with good ones. The WBT midline series is
surprisingly inexpensive and good quality, as is the Vampire line (my
value favorite in the world of high-grade connectors)
Check out Markertek at www.markertek.com or 1-800-522-2025 for pricing
($US 3 or 4 each I think) and availability.
best of luck,
Aaron
___________________________________________________________
Aaron Bohnen, B.A.Sc., E.I.T. email: bohnen@unixg.ubc.ca
- -Ph.D. Candidate, Civil Engineering Department, U.B.C.
- -Technicraft Engineering Services
=========================================================================
From: Dave Stagner <dstagner@icarus.net>
Subject: Re: CAT5 speaker cable? & connectors
Date: Fri, 20 Feb 1998 13:10:58 -0600 (CST)
Source: Sound Digest Archive v01.n197
Speaking of RCA connectors, does anyone know of a high-quality, affordable
RCA plug that is small enough to fit the close-spaced jacks of vintage
tube gear? All those Cardas and other plugs designed to work with
undersea-sized cables just don't fit, leading to poor connections.
Also, any suggestions on cleaning corroded vintage contacts?
- -dave
Practice beautiful randomness and act kind of senseless.
<dstagner@icarus.net>
=========================================================================
From: Richard C Nevill <rnevill@is.dal.ca>
Subject: Re: CAT5 speaker cable? & connectors
Date: Fri, 20 Feb 1998 21:32:14 -0400 (AST)
Source: Sound Digest Archive v01.n197
On Fri, 20 Feb 1998, Aaron Bohnen wrote:
> Hi Dave,
>
>
> Check out Markertek at www.markertek.com or 1-800-522-2025 for pricing
> ($US 3 or 4 each I think) and availability.
Parts Connection also has 'em (www.sonicfrontiers.com/TPC) or
1-800-769-0747 or Micheal Percy (whose catalog I don't have handy) has a
good selection of RCA's for both ends
Cheers
Richard Nevill
>
> best of luck,
>
> Aaron
> ___________________________________________________________
> Aaron Bohnen, B.A.Sc., E.I.T. email: bohnen@unixg.ubc.ca
> -Ph.D. Candidate, Civil Engineering Department, U.B.C.
> -Technicraft Engineering Services
>
=========================================================================
From: "Owen Young" <oyoung@clear.net.nz>
Subject: CAT5 speaker cable? & connectors
Date: Sat, 21 Feb 1998 07:02:15 -1200
Source: Sound Digest Archive v01.n197
Guys,
May I suggest Cardas connectors which are rhodium plate over silver plate
over machined solid brass (rhodium giving a hard & non oxidising finish to
the silver, with, if recall correctly, better conductive & arguably better
sonic properties to gold plate.) Prices, eg US$16 for RCA plug prs from
Michael Percy. Plain silver over brass is also avail at US$14/pr. Design &
construction is also v impressive.
Owen
Owen Young
Auckland, New Zealand
oyoung@clear.net.nz
=========================================================================
From: "Owen Young" <oyoung@clear.net.nz>
Subject: Re: CAT5 speaker cable? & connectors
Date: Sat, 21 Feb 1998 10:08:39 -1200
Source: Sound Digest Archive v01.n197
>The WBT midline series is
> surprisingly inexpensive and good quality, as is the Vampire line (my
> value favorite in the world of high-grade connectors)
Indeed, Vampire is one snooty audiophile brand that is relatively
inexpensive. ($10.50pr RCA sockets, Michael Percy). Cu/Ag/Au plating on
brass, they advertise.
When looking at plugs, look for one piece assemblies(for ea leg) rather
than multiple piece jointed internal construction.
However, IMO the best connector is no connector. I have often found that
bare wire(providing you control the oxidation problem) sounds better than
adding connections and connectors and/or solder.
Also those large massy connectors(esp brass) interrupting a nice copper(or
silver) conductor is not necessarily a good idea.
Rememember Cogan Hall had those copper tube conductors which plugged
straight into RCA sockets and into binding posts?
And the flat ribbon conductors like Goertz which require no plugs?
Tired of coloured, commercial cables, for years I've used homemade cable
constructed from polyurethane enamelled transformer winding copper wire, ie
solid core, but in a multiple core +/-/+/- configuration spaced and
spiralled around a plastic tube, ie air dielectric mostly, no screening or
wrapping. Around 21-22AWG ea strand. A wonderfully open, fatigue free,
transparent interconnect esp. Plugs were cheapo, but one piece, low mass,
short signal path!
Food for thought
Owen
Owen Young
Auckland, New Zealand
oyoung@clear.net.nz
=========================================================================
From: Peter Drake <peterd@ndsuk.com>
Subject: Re: CAT5 speaker cable? - now Whamodynes
Date: Tue, 17 Feb 1998 09:49:12 +0000
Source: Sound Digest Archive v01.n194
Bottlehead wrote:
>
> > Second, i'm thinking of using it for internal wire for speakers (i'm
> going
> > to build a pair of Superwhamos). Anyone compared it to Bottlehead's
> > recommended 12ga house wire in this configuration?
>
> The 12 ga. is long since gone, except I guess there's still some hooked to
> the subs (about 4 inches).
> I had good luck with 18 ga. solid on the mids and 22 ga. solid on the
> highs. If you're really macho, strip the insulation off and run the wire
> butt nekked. I bet a Solo inductor, unwound and wrapped with teflon
> plumbing tape would make good internal wire too.
> Next sperment will be Jena 18 ga. Hookup, mighty nice stuff, but $$$ for
> all the wire you need to hook all them mids together.
>
> (speaking of
> > Superwhamos, has anyone tried vintage oil caps for the crossover? I have
> > a bunch of 200v 1% Southeastern and CDE caps to try)
>
> Yeah, they work great. I used two 3 mfd GE motor start caps in parallel on
> the tweet, and that setup whupped both a 6 mfd ($$!) Hovland and a 6.8 mfd
> Black Gate soundly.
>
> By the way, don't build the Supers, build the Hypers, with the tapered pipe
> enclosure. Coat the mids and tweets with Ennemoser Lack, line the cabinets
> with felt, stuff the pipes lightly (maybe 1/4 lb.) with real wool. Stuff
> the back chamber of the sub with 1 lb. fiberfill. Use a thick (1-1/2")
> front baffle, and round the edges, maybe 1-1/2" radius if possible. Open up
> the tweet and put a 3/8" dot of felt on the pole piece, and put a small
> square of foam on top of it. Use Andy Bartha's small Whatchamacallits
> between the tower and the sub.
>
> Try about 10W SE.
>
> Doc B.
You've depressed me now Doc, I've just put together my Super-Whamodynes
!
No glue, cabinets not sealed, drive units not sealed to cabinets, very
thin multistrand wire for all drivers and just roughly connected to the
usual speaker cable using Michell plugs. Standing on carpet with no
feet.
4 mH air core inductor and 1.5microF metal foil cap in crossover.
No damping of any kind in cabinets, which are still bare MDF (22mm
except
for the baffles which are 18mm).
How do they sound ?
I'm stunned that something so obviously quickly out together and
unfinished
can sound so good. They seem clearer, more dynamic and with a deeper
(although
not "as much") bass as my KEF R104.2s. This is just on a brief listen (I
only
built the second sub last night) from a cheap portable CD player through
a Yamaha AV pre-amp and an Incatech pre-amp (both ss) feeding my Leak
Stereo 20
(I'll be trying LP tonight).
They rattle a bit at very high volumes, but I guess that's because the
wire
hasn't been routed properly and the drivers have only been fixed with 2
screws
each (except the subs) so I don't thread the MDF.
What should I use to line the cabinets (I don't like the idea of using
fibre glass like you suggest as my wife gets asthma) ?
Would the egg-box style packing foam strips be OK ?
Are the Hypers that much better than the Supers ?
I'm very impressed at the moment and looking forward to getting them
"finished".
Well worth the subscription to VALVE.
Thanks Doc
- --
Pete Drake
peterd@ndsuk.com
http://www.ndsworld.com
=========================================================================
From: "Bottlehead" <Bottlehead@prodigy.net>
Subject: Re: CAT5 speaker cable? - now Whamodynes
Date: Tue, 17 Feb 1998 08:47:03 -0800
Source: Sound Digest Archive v01.n195
> You've depressed me now Doc, I've just put together my Super-Whamodynes
> !
Hey, it's still a good speak. You can always change to the tapered pipe
later.
> 4 mH air core inductor and 1.5microF metal foil cap in crossover.
First thing to do is change to a 6 mfd cap.
No, wait. First thing to do is read Feb 97. That has the most current setup
for the towers.
Then change the cap to 6 mfd, and do the treatment of the tweeter I
mentioned in the last e-mail. The tweet may seem a bit bright until it
breaks in with this bigger cap, but it will ultimately give much better
presence.
> can sound so good. They seem clearer, more dynamic and with a deeper
> (although
> not "as much") bass as my KEF R104.2s.
Seal them up!
The tapered pipes will give a better perceived response in the lower
midrange/upperbass, where the vented box's response can be just a bit shy.
But leaving either cabinet full of holes and cracks just makes them into
open baffles.
Also, let them break in. I suspect you will be telling me the subs have too
much bass in a month or two. eXperiment with wiring the subs in and out of
phase with the towers. In phase is clearly better with the pipes, but out
of phase can sound better with the vented boxes in some situations, due to
the somewhat different rolloff of the vented vs. the tapered pipe
enclosure.
> They rattle a bit at very high volumes, but I guess that's because the
> wire
> hasn't been routed properly and the drivers have only been fixed with 2
> screws
> each (except the subs) so I don't thread the MDF.
You may also want to try rotating the mids 180 degrees. I have seen two
drivers out of maybe 100 that buzzed slightly at high volume levels. These
were early units, I haven't had the problem except in the original batch,
and I currently drive them with up to 25W with no rattling at all.
>
> What should I use to line the cabinets (I don't like the idea of using
> fibre glass like you suggest as my wife gets asthma) ?
> Would the egg-box style packing foam strips be OK ?
I now use inexpensive (like $3/sq. yd.) "felt" carpet pad. It's actually
synthetic. I even use this stuff on a couple of the walls in my listening
room, to great effect. LynnO says this stuff is nowhere near as good as
real felt, so if you happen to own a haberdashery, you might want to try
real wool felt.
I've heard a pair of Superwhamos that were lined with the egg crate foam,
and thought the felt was superior.
>
> Are the Hypers that much better than the Supers ?
Only in the upper bass/lower midrange. I was very surprise to find super
flat response from 100Hz to 1kHz with the pipes, the flattest I'd ever
seen. The vented boxes had a bit of a dip around 300-400 Hz as I recall.
Doc B.
=========================================================================
From: darmah@goodnet.com
Subject: Catalog collectors-Lowther
Date: Sun, 8 Mar 1998 11:22:28 +0000
Source: Sound Digest Archive v01.n210
Hi Joeneters:
In case any one is interested I have about 15 copies of Audio
Techniks latest Lowther catalog. IN GERMAN!!!!!!
Nice pics.
This might be an interesting item for those of you who collect Audio
lit from around the world.
Theyr'e $5.- so if you'd like one email me privatly and I'll give you
my address.
Again they're in GERMAN! Sorry no pricelist but you can check thier
website for that.
Best Regards
Marc S. Wauters
darmah@goodnet.com
Internet Paging: "http://wwp.mirabilis.com/544722"
My Home Page: "http://www.goodnet.com/~darmah/"
=========================================================================
From: "Reid Welch" <rewelch@earthlink.net>
Subject: cathode coating failure
Date: Tue, 18 Aug 1998 02:38:32 -0400
Source: Sound Digest Archive v01.n394
I was just examining a failed Silvertone globe 24 (pre "24A") dating from
about 1929. It had a cathode to grid short. Breaking off the glass exposed
the mode of failure: The chalky cathode coating had peeled one spot like old
paint, the curl pressing on the grid stanchion. Probing that area with a
pin showed there was little adhesion to the nickel cathode in the area
surrounding the peel. The other portions of the cathode showed the
chalk-like coating to be well attached.
I guess everyone has seen cathode coatings flaking off- especially off of
early DHTs and filimentary rectifiers. Sometimes it's the failure mode of
new tubes, too. I assume this physical stripping is primarily due to
imperfect cathode etching. If the substrate doesn't have a really good
mechanical or chemical bond to the coating it's likely to flake off in time.
I wonder if high voltage hitting a cold cathode is really the main culprit?
I don't know. It's easy to visualize coating failure caused by the
temperature-related expansion of a nickel IDH sleeve or DHT filament. My
hypothesis says that thermal expansion lifts or weakens the chalky coating
if the coating _was not well bonded in the first place_. If true, a tube
suffers some punishment each time it warms up, even with delayed B+. Early
80's often evidence considerable stripping, but no more (in my limited
experience) than DHTs of the period. -And DHT's don't get hit with B+ as
fast as the rectifier.
In summary, I wonder if cathode stripping of the flaky kind you actually see
by tipping and tapping the tube- is related to poor quality control and the
inherent expansion of cathode substrate; whether expansion and poor bonding
is more to be blamed for flaking than blaming high voltage hitting a cold
cathode. The latter abuse seems more liable to "poison" the cathode through
ion bombardment than to physically chip away at the coating. Whatever, a
cathode doesn't have to suffer visible "stripping" (this seems to be a
catch-all term) to become permanently impaired.
Any other views?
Reid
=========================================================================
From: Grego Sanguinetti <grego@lscpdx.latticesemi.com>
Subject: Re: cathode coating failure
Date: Tue, 18 Aug 1998 10:13:01 -0700
Source: Sound Digest Archive v01.n394
Reid pointed out...
> In summary, I wonder if cathode stripping of the flaky kind you actually see
> by tipping and tapping the tube- is related to poor quality control and the
> inherent expansion of cathode substrate; whether expansion and poor bonding
> is more to be blamed for flaking than blaming high voltage hitting a cold
> cathode. The latter abuse seems more liable to "poison" the cathode through
> ion bombardment than to physically chip away at the coating. Whatever, a
> cathode doesn't have to suffer visible "stripping" (this seems to be a
> catch-all term) to become permanently impaired.
>
> Any other views?
It seems quite reasonable that the flaking is most largely due to
materials and construction weakness and flaws.
yes, I would guess that rappid application of filament current
does more to exacerbate the condition than the application of plate
voltage prior to complete filament warming. Especially if the filament
supply is DC.
I think next time I see a cathode/grid short on an old valuable
tube I will try to get some extra life out of it by applying current
across the short. It seems that in a case like this you may be
able to burn the short open. Worth a try anyway.
- -grego
=========================================================================
From: Thomas Danley <Tom@ppci.com>
Subject: Re: cathode coating failure
Date: Tue, 18 Aug 1998 13:24:44 -0500
Source: Sound Digest Archive v01.n394
Grego Sanguinetti wrote:
> Reid pointed out...
>
> > In summary, I wonder if cathode stripping of the flaky kind you actually see
> > by tipping and tapping the tube- is related to poor quality control and the
> > inherent expansion of cathode substrate; whether expansion and poor bonding
> > is more to be blamed for flaking than blaming high voltage hitting a cold
> > cathode. The latter abuse seems more liable to "poison" the cathode through
> > ion bombardment than to physically chip away at the coating. Whatever, a
> > cathode doesn't have to suffer visible "stripping" (this seems to be a
> > catch-all term) to become permanently impaired.
> >
> > Any other views?
>
> It seems quite reasonable that the flaking is most largely due to
> materials and construction weakness and flaws.
>
> yes, I would guess that rappid application of filament current
> does more to exacerbate the condition than the application of plate
> voltage prior to complete filament warming. Especially if the filament
> supply is DC.
>
> I think next time I see a cathode/grid short on an old valuable
> tube I will try to get some extra life out of it by applying current
> across the short. It seems that in a case like this you may be
> able to burn the short open. Worth a try anyway.
>
> -grego
A possibly usefull tidbit, when I used to work at the TV store (1968-71)
after high school, we had a Tube rejuvinator which could do several things.
It had a discharge button which blasted open heater cathode shorts, it also had a
feature the briefly raised the filiment voltage a bunch which was suppose to
re-juvinate the cathode coating (somehow). Some times the thing worked well some
times it didn't work at all.
Then when I worked at Grommes Precision, Al Hart (the head designer) said
"them dang things don't work at all" and poo poo'd the acounts from the TV store.
If a tube didn't check A-ok it went home to become an air rifle target (I still
have a decent sized box of funky 6GT5 output tubes).
Tom
=========================================================================
From: An-shyang Chu <achu@sandia.gov>
Subject: Re: cathode coating failure
Date: 18 Aug 1998 13:45:30 -0600
Source: Sound Digest Archive v01.n394
Reid says
>..... <snip>
>
>I guess everyone has seen cathode coatings flaking off- especially off of
>early DHTs and filimentary rectifiers. Sometimes it's the failure mode of
>new tubes, too. I assume this physical stripping is primarily due to
>imperfect cathode etching. If the substrate doesn't have a really good
>mechanical or chemical bond to the coating it's likely to flake off in time.
>I wonder if high voltage hitting a cold cathode is really the main culprit?
>I don't know. It's easy to visualize coating failure caused by the
>temperature-related expansion of a nickel IDH sleeve or DHT filament
>.... <snip>
Talking to Jac at AVVT, the filament failure is mostly due to re-crystallization
of the substrate nickel through thermal annealing (e.g. inrush current heating).
I am sure that poor bonds between the oxide (Barium?) and nickel surface did not
help either. Thermal expansion, if any, might be a small secondary effect? I
think the impurity in the nickel might also contribute to the failure as well.
My $0.02.
Best regards,
hopper
.
=========================================================================
From: Douglas Purl <dcp@selway.umt.edu>
Subject: Re: cathode coating failure
Date: Tue, 18 Aug 1998 16:22:07 -0600 (MDT)
Source: Sound Digest Archive v01.n394
I cannot pinpoint the date or the year, but back in tube days I recall
either a chapter of a book or a magazine article entitled something like
"The Chemistry of Vacuum Tubes." It's an obvious topic for the tube
industry to have investigated in its heyday/hayday/salad days.
Would that the websystem someday makes available all the lore of the past.
It would require lunch change for the philantropist W. Gates to sponsor
same and would make the internet the central library of the world.
Doug Purl
=========================================================================
From: Rick Francis <rfranci@uoft03.utoledo.edu>
Subject: Re: cathode coating failure
Date: Wed, 19 Aug 1998 10:12:22 -0400 (EDT)
Source: Sound Digest Archive v01.n395
On Tue, 18 Aug 1998, Douglas Purl wrote:
> Would that the websystem someday makes available all the lore of the past.
> It would require lunch change for the philantropist W. Gates to sponsor
> same and would make the internet the central library of the world.
>
Gates is spending more than lunch change to acquire/create a digital art
library. Ten years ago I knew an art historian working at Microsoft as
part of this project, and I suspect it is steaming ahead. I probably don't
need to mention that so far Gates has shown no indication of doing this
for philanthropic motives. What he's getting will cost you, piece by
piece.
Compared to the Carnegies and Mellons, the new super-rich have been
remarkably indifferent to building public-service institutions -- and that
includes monuments to themselves. Certainly NOTHING along the lines of the
Free Public Libraries that dot the country. One of Bill G.'s colleagues
(Allen?) built an enormous wing onto the Univ. of Washington library, but
big as it is, it's still just local.
Wouldn't you think Gates, just out of self-interest, would donate
internet-access machinery (computers and hookups etc.) to public
libraries, making sure that the general public becomes accustomed to
Windows/Microsoft software, while looking like a solid
citizen-philanthropist?
Rick
=========================================================================
From: Grover Gardner <groverg@postoffice.att.net>
Subject: Cathode follower drive
Date: Sun, 28 Jun 1998 11:34:25 -0500
Source: Sound Digest Archive v01.n325
Tom Ronan and another friend have been encouraging me to try a
direct-coupled cathode follower to drive my output triodes for a while,
before I settled on the final build for these amps, so long in the making
:-). I spent the better part of last weekend figuring out how it works (I
am NOT a math whiz) and studying the Ongaku circuit in SP, Diego Nardi's
Hidotrac also from SP, jc's first Dinosaur and some other similar circuits.
This other friend uses 7119 or 6900--I have some 7044s and 5687s, so I
thought I've give it a go.
First I tried a little diode-rectified balanced +/- supply, +170/-170,
fiddled with the load resistor value to get -75 volts on the output tube's
grid, and so forth. Well, the balanced supply was very hard to get just
right, but after I did I sat back for a listen. I used the 5687, which is
a tube I've always had trouble liking but I noticed that the Ongaku circuit
runs these tubes at lower current than one might expect, so I tried to do
the same. At first the sound was much what I feared it would be--very
sweet and clean, but also lacked depth (of soundstage) and character. I
forced myself to keep fiddling with it for a few days, taking the plate
supply off the main, tube-rectified B+ and keeping the diode-rectified
negative supply, trying different decoupling and coupling caps, different
types of resistors, etc.
What I wound up with is a parallel 12AT7 driving a 5687 plate follower cap
coupled to a 5687 CF direct-coupled to the output grids, with a bias pot to
adjust the 5687 grid bias. What I'm hearing is warm, 3-D, powerful and
immensely musical, with none of the flatness or blandness I feared. The
7044 in this situation sounded too clangy, but I understand the 7119 is the
better tube so I'll try it when I get my hands on a pair.
What's kinda fun about the way it's set up is that I can drop a 12AU7 in
place of the 12AT7 for less gain and a different tone with no penalty or
changes. I have not direct-coupled the first two stages, a la Ongaku,
since my B+ is somewhat lower, though perhaps with a different input tube
(5965?) this would be possible. I have also not tried an SRPP at the input
stage, since again I have never had success with this, but maybe some
fooling around would get me better results here too. In which case I guess
I'll just ahve the Ongaku circuit for the most part and I won't be able to
claim one smidgen of originality on my part :-).
This is old news to some, but I thought I'd report the happy results for
this learner.
Grover Gardner
groverg@postoffice.att.net
=========================================================================
From: Grover Gardner <groverg@postoffice.att.net>
Subject: Re: Cathode follower drive
Date: Sun, 28 Jun 1998 22:18:10 -0500
Source: Sound Digest Archive v01.n326
At 8:55 AM +0800 6/29/98, Johari Yip wrote:
>Grover
>
>Nice to hear your having fun the past weekend. What the triode you're
>driving?
>The 5687s likes low voltage, high current to sound good which I guess you
>would know by now. I've heard a lot about running CF by +/- HV and it's
>suppose to be superior to conventional B+ / grd in term of voltage swing
>and drive for the next stage.
>Maybe you would or fellow joenetter comment on this.
The exciting thing about the CF is that it made every output tube I tried
sound terrific. The VV52s of course I mostly use. But I tried a Valve
Arts 5300 and it sounded fantastic here, in fact I'm not sure that I didn't
prefer it to the VV52 (good news, eh, Doc?). It's more recessed in the
soundstage than the VV52, less forward in imaging, but it had a very
refined, ingratiating character. Of course a stock 300B sounded marvelous,
if it didn't have quite the depth and weight of the others.
But are you saying that a separate, balanced +/- supply allows better
voltage swing than taking the plate off the main B+ and using a separate
negative supply? Or just that using any form of +/- arrangement is an
improvement, as opposed to grounding the cathode load? It was only when I
took the plate supply off the main B+ that the sound started to loosen up
and get acceptable to my ears--of course, I still have a healthy negative
supply to bias the VV52 grid. I'm not able to measure the voltage output
of the driver stage, but I'll see if I can arrange some tests. I'd be
interested to hear more about this.
As for operating points, I've experienced the opposite. It was only after
trying something close to the Ongaku operating points, higher Vp and lower
current, that I've come to like this tube. The Ongaku runs the 5687 CF at
250 Vp and about 7 mA, if my calculations are correct.
Grover Gardner
groverg@postoffice.att.net
=========================================================================
From: "Johari Yip" <hfyip@pacific.net.sg>
Subject: Re: Cathode follower drive
Date: Mon, 29 Jun 1998 08:55:49 +0800
Source: Sound Digest Archive v01.n326
Grover
Nice to hear your having fun the past weekend. What the triode you're
driving?
The 5687s likes low voltage, high current to sound good which I guess you
would know by now. I've heard a lot about running CF by +/- HV and it's
suppose to be superior to conventional B+ / grd in term of voltage swing
and drive for the next stage.
Maybe you would or fellow joenetter comment on this.
Johari
- ----------
> From: Grover Gardner <groverg@postoffice.att.net>
> To: 'sound@mail.tpoint.net' <sound@deliverator.io.com>
> Subject: Cathode follower drive
> Date: Monday, June 29, 1998 12:34 AM
>
> Tom Ronan and another friend have been encouraging me to try a
> direct-coupled cathode follower to drive my output triodes for a while,
> before I settled on the final build for these amps, so long in the making
> :-). I spent the better part of last weekend figuring out how it works
(I
> am NOT a math whiz) and studying the Ongaku circuit in SP, Diego Nardi's
> Hidotrac also from SP, jc's first Dinosaur and some other similar
circuits.
> This other friend uses 7119 or 6900--I have some 7044s and 5687s, so I
> thought I've give it a go.
>
> First I tried a little diode-rectified balanced +/- supply, +170/-170,
> fiddled with the load resistor value to get -75 volts on the output
tube's
> grid, and so forth. Well, the balanced supply was very hard to get just
> right, but after I did I sat back for a listen. I used the 5687, which
is
> a tube I've always had trouble liking but I noticed that the Ongaku
circuit
> runs these tubes at lower current than one might expect, so I tried to do
> the same. At first the sound was much what I feared it would be--very
> sweet and clean, but also lacked depth (of soundstage) and character. I
> forced myself to keep fiddling with it for a few days, taking the plate
> supply off the main, tube-rectified B+ and keeping the diode-rectified
> negative supply, trying different decoupling and coupling caps, different
> types of resistors, etc.
>
> What I wound up with is a parallel 12AT7 driving a 5687 plate follower
cap
> coupled to a 5687 CF direct-coupled to the output grids, with a bias pot
to
> adjust the 5687 grid bias. What I'm hearing is warm, 3-D, powerful and
> immensely musical, with none of the flatness or blandness I feared. The
> 7044 in this situation sounded too clangy, but I understand the 7119 is
the
> better tube so I'll try it when I get my hands on a pair.
>
> What's kinda fun about the way it's set up is that I can drop a 12AU7 in
> place of the 12AT7 for less gain and a different tone with no penalty or
> changes. I have not direct-coupled the first two stages, a la Ongaku,
> since my B+ is somewhat lower, though perhaps with a different input tube
> (5965?) this would be possible. I have also not tried an SRPP at the
input
> stage, since again I have never had success with this, but maybe some
> fooling around would get me better results here too. In which case I
guess
> I'll just ahve the Ongaku circuit for the most part and I won't be able
to
> claim one smidgen of originality on my part :-).
>
> This is old news to some, but I thought I'd report the happy results for
> this learner.
>
>
> Grover Gardner
> groverg@postoffice.att.net
>
=========================================================================
From: "Johari Yip" <hfyip@pacific.net.sg>
Subject: Re: Cathode follower drive
Date: Mon, 29 Jun 1998 12:28:47 +0800
Source: Sound Digest Archive v01.n326
- ----------
> From: Grover Gardner <groverg@postoffice.att.net>
> To: Johari Yip <hfyip@pacific.net.sg>; 'sound@mail.tpoint.net'
<sound@deliverator.io.com>
> Subject: Re: Cathode follower drive
> Date: Monday, June 29, 1998 11:18 AM
> The exciting thing about the CF is that it made every output tube I tried
> sound terrific. The VV52s of course I mostly use. But I tried a Valve
> Arts 5300 and it sounded fantastic here, in fact I'm not sure that I
didn't
> prefer it to the VV52 (good news, eh, Doc?). It's more recessed in the
> soundstage than the VV52, less forward in imaging, but it had a very
> refined, ingratiating character. Of course a stock 300B sounded
marvelous,
> if it didn't have quite the depth and weight of the others.
>
> But are you saying that a separate, balanced +/- supply allows better
> voltage swing than taking the plate off the main B+ and using a separate
> negative supply? Or just that using any form of +/- arrangement is an
> improvement, as opposed to grounding the cathode load? It was only when
I
> took the plate supply off the main B+ that the sound started to loosen up
> and get acceptable to my ears--of course, I still have a healthy negative
> supply to bias the VV52 grid. I'm not able to measure the voltage output
> of the driver stage, but I'll see if I can arrange some tests. I'd be
> interested to hear more about this.
Precisely, equal HV +/- on the plate and cathode with grid biasing of the
next stage. I've had experience with CF using B+ connected to the plate and
a cathode bias resistor connected to Grd and so far didn't have good
result. IMHO, the sound is very flat with very little substance in it's
presentation. Talking about a 12AU7 here, maybe it's the character of the
tube itself.
>
> As for operating points, I've experienced the opposite. It was only
after
> trying something close to the Ongaku operating points, higher Vp and
lower
> current, that I've come to like this tube. The Ongaku runs the 5687 CF
at
> 250 Vp and about 7 mA, if my calculations are correct.
I'm using the 5687 in the linestage at 150Vp and 15mA trotal for both
triode half and as a anode follower/voltage amplifier. Is there a
difference here?
>
>
> Grover Gardner
> groverg@postoffice.att.net
>
Johari
=========================================================================
From: "T. Loesch" <ezee_e@hotmail.com>
Subject: Re: Cathode follower drive
Date: Mon, 29 Jun 1998 04:54:55 PDT
Source: Sound Digest Archive v01.n327
Yo Dudettes and Dudes,
>What I wound up with is a parallel 12AT7 driving a 5687 plate
>follower cap coupled to a 5687 CF direct-coupled to the output grids,
>with a bias pot to adjust the 5687 grid bias.
Interesting.
>What I'm hearing is warm, 3-D, powerful and immensely musical,
>with none of the flatness or blandness I feared.
Did you ever use something like a choke loaded 2A3 as Driver? How did it
compare....
>I have also not tried an SRPP at the input stage, since again I
>have never had success with this, but maybe some fooling
>around would get me better results here too. In which case I
>guess I'll just ahve the Ongaku circuit for the most part and I
>won't be able to claim one smidgen of originality on my part :-).
The most interesting thing about the Ongaku is that it does not really
use a SRPP Input.... Sure it uses a "Totem-Pole" Configuration, but the
upper Valve is working as Current-Source with the Output from the lower
valves Anode and not from the Upper Valves Cathode.... Hence the upper
Cathode follower is eliminated....
It's not particulary usefull doing this in Line-Stages or at the Final
Driver to the valve (high Output Z), but i think for an Input Stage it
might be a viable solution....
Lynn has got some interesting Graphs on his Web-Site for the various
Connection Options in "SRPP" (and X-Former Coupling)....
http://www.teleport.com/~lynno/HD357.gif
http://www.teleport.com/~lynno/HD246.gif
Kind regards Thorsten.
======================================
e-mail:
Thorsten@tnt-audio.com
Visit TNT-Audio on the Web - the only advertising
free audio web-zine.
http://www.tnt-audio.com
======================================
______________________________________________________
Get Your Private, Free Email at http://www.hotmail.com
=========================================================================
From: "T. Loesch" <ezee_e@hotmail.com>
Subject: Re: Cathode follower drive
Date: Mon, 29 Jun 1998 08:32:58 PDT
Source: Sound Digest Archive v01.n327
Hi there,
>Oh, I've choke-loaded everything from a 2A3 to the kitchen sink :-).
How did the Kitchen Sink sound with that? Dynamic and Three Dimensional
;-).
>My original intent was to build a three-stage amp using a
>choke-loaded driver with a simple gain stage in front, producing
>full gain without a preamp (tall order).
Well, I do have a Preamp (because I listen to Vinyl - a direct-Input Amp
is good if Seedee is your main source, but if it is Vinyl a Pre/Power
solution seems better to me). This will easily do 2-3V into 10k, so no
Gain-Problems here....
As I'm slowly reving up for my 211 Stereo Amp project, I'm really
intersted in this thread. I have narrowed down my choice of Driver to
two possible Topologies:
1) Ongaku
2) Ciro Marzio's Orpheo in a Version 1.5 sort of (417A into 2A3 choke
loaded - fixed bias into 211 fixed Bias)
Either version will use a Choke Input Filter PSU for +B though (kinda
scary though at +1250V +B......)......
I'm not sure, but I might end up using 211's as Rectifiers too....
>Even more interesting was a fixed-bias 6A5G.
What is that one? 6A5G? Is that a 6V Filament Version?
>Space,
Final Frontier. But not for a Pair of 211 Mono's.... They have to be
BIG.
>tube availability,
Seems the Sovtek 6B4G looks like a good bet....
>bandwidth,
Should not be such a big Problem. I intend to mod a normal EL84/34 PP
OPT into a Anode Choke. The X-Former I intend to use has a Primary
Resonace of 80kHz.... Should be good enough....
>power supply requirements,
Well. If I start with a 1250V Choke Input Supply, the rest sort of
fades.... And a good Bipolar Supply for the Cathode Follower is nothing
be sniffed at either....
>gain factors,
I don't need that much....
>*sound*--
Now that is the interesting bit....
Then of course there is the Question of which source you are using....
>More importantly, I wanted to learn more about using tubes! :-)
Ahhh well. I did that about 15 Years ago. I just want results....
>A tube like the 2A3 or 45 doesn't need help--on its own it is a
>beautiful reproducer of musical tones. Do as little to it as possible
>and it will sound beautiful.
Do I read "Drive it from a Low Impedance Input Stage and load it with a
Choke in Cathode (or fixed - I conceptually prefer Fixed) Bias..."
correctly?
>This is why, from an educational point of view, I have become
>interested in designs like the Ongaku, which use tubes in a very
>creative way.
Yes. I noticed.... The Ongaku is also one of the best Ways I ever heard
to Drive Speakers like my ones....
ThanX for Your Input so far and keep me posted please....
My Parts for the start of the 211 Project should be with me at beginning
of August (found a good deal on used stuff relatively near me -
Holland)....
Kind regards Thorsten.
======================================
e-mail:
Thorsten@tnt-audio.com
Visit TNT-Audio on the Web - the only advertising
free audio web-zine.
http://www.tnt-audio.com
======================================
______________________________________________________
Get Your Private, Free Email at http://www.hotmail.com
=========================================================================
From: Grover Gardner <groverg@postoffice.att.net>
Subject: Re: Cathode follower drive
Date: Mon, 29 Jun 1998 10:29:21 -0500
Source: Sound Digest Archive v01.n327
At 4:54 AM -0700 6/29/98, T. Loesch wrote:
>Yo Dudettes and Dudes,
>
>>What I wound up with is a parallel 12AT7 driving a 5687 plate
>>follower cap coupled to a 5687 CF direct-coupled to the output grids,
>>with a bias pot to adjust the 5687 grid bias.
>
>Interesting.
>
>>What I'm hearing is warm, 3-D, powerful and immensely musical,
>>with none of the flatness or blandness I feared.
>
>Did you ever use something like a choke loaded 2A3 as Driver? How did it
>compare....
Oh, I've choke-loaded everything from a 2A3 to the kitchen sink :-). My
original intent was to build a three-stage amp using a choke-loaded driver
with a simple gain stage in front, producing full gain without a preamp
(tall order). The most successful version was a 12AT7/46/VV52, a really
beautiful sound, good gain and a warm, natural, liquid sound. Even more
interesting was a fixed-bias 6A5G. But I ran into several limitations
here--in fixed bias one is ostensibly limited to 50K grid resistance,
combined with the drive demands of the 2A3/6A5G itself, which are nothing
to spit at.
I got some maginificent sounds from a choke-loaded driver, and my friends
and audio "consultants" wondered why I kept pushing on. But it seemed like
every way I turned, I hit a roadblock that kept me from taking the design
further, or achieving the goals I wanted to meet. Space, tube
availability, bandwidth, power supply requirements, gain factors,
*sound*--all these things weighed on my mind as I tried to sort out what I
really wanted from these amps.
More importantly, I wanted to learn more about using tubes! :-)
It seems to me at this point that there are two ways (at least) to look at
tubes. A tube like the 2A3 or 45 doesn't need help--on its own it is a
beautiful reproducer of musical tones. Do as little to it as possible and
it will sound beautiful. OTOH, there is the tube as a transconduction
device--a means to an end--and though a particular tube may not have an
inherent beauty of its own, there might be a way to manipulate it to make
it serve the desired purpose--to transmit musical tones in a convincing
way. As I struggled along, I got more and more interested in
high-transconductance devices, what they are capable of, and how they might
be manipulated to create music.
This is why, from an educational point of view, I have become interested in
designs like the Ongaku, which use tubes in a very creative way.
>The most interesting thing about the Ongaku is that it does not really
>use a SRPP Input.... Sure it uses a "Totem-Pole" Configuration, but the
>upper Valve is working as Current-Source with the Output from the lower
>valves Anode and not from the Upper Valves Cathode.... Hence the upper
>Cathode follower is eliminated....
This is correct, thank you for pointing it out. I will take a closer look
at this topology, it appeals to me more than a cathode-output.
>
>It's not particulary usefull doing this in Line-Stages or at the Final
>Driver to the valve (high Output Z), but i think for an Input Stage it
>might be a viable solution....
>
>Lynn has got some interesting Graphs on his Web-Site for the various
>Connection Options in "SRPP" (and X-Former Coupling)....
>
>http://www.teleport.com/~lynno/HD357.gif
>
>http://www.teleport.com/~lynno/HD246.gif
Thanks for your interest and comments, Thorsten, very good food for thought.
Grover Gardner
groverg@postoffice.att.net
=========================================================================
From: Grover Gardner <groverg@postoffice.att.net>
Subject: Re: Cathode follower drive
Date: Mon, 29 Jun 1998 10:35:07 -0500
Source: Sound Digest Archive v01.n327
At 12:28 PM +0800 6/29/98, Johari Yip wrote:
>Precisely, equal HV +/- on the plate and cathode with grid biasing of the
>next stage. I've had experience with CF using B+ connected to the plate and
>a cathode bias resistor connected to Grd and so far didn't have good
>result. IMHO, the sound is very flat with very little substance in it's
>presentation. Talking about a 12AU7 here, maybe it's the character of the
>tube itself.
This has been my experience, which is why this particular circuit has been
a revelation to me.
>>
>> As for operating points, I've experienced the opposite. It was only
>after
>> trying something close to the Ongaku operating points, higher Vp and
>lower
>> current, that I've come to like this tube. The Ongaku runs the 5687 CF
>at
>> 250 Vp and about 7 mA, if my calculations are correct.
>
>I'm using the 5687 in the linestage at 150Vp and 15mA trotal for both
>triode half and as a anode follower/voltage amplifier. Is there a
>difference here?
To my ears there is an enormous difference. I have never loved the 5687
very much, run at such an operating point. Used a la Ongaku, however, it
seems to have an entirely different character, much sweeter and "liberated".
Interestingly, this weekend I tried paralleling all sections--12AT7, 5687
and 5687 CF. The difference was pretty shocking--extreme, almost
frightening clarity, an incredibly potent, powerful sound. In fact, really
too much, I thought. Not very relaxing to listen to, but certainly
revealing!
Grover Gardner
groverg@postoffice.att.net
=========================================================================
From: Grover Gardner <groverg@postoffice.att.net>
Subject: Re: Cathode follower drive
Date: Mon, 29 Jun 1998 14:42:16 -0500
Source: Sound Digest Archive v01.n327
At 8:32 AM -0700 6/29/98, T. Loesch wrote:
Thorsten, I'll pass along my experiences over the past year for what they
are worth.
>Hi there,
>
>>Oh, I've choke-loaded everything from a 2A3 to the kitchen sink :-).
>
>How did the Kitchen Sink sound with that? Dynamic and Three Dimensional
>;-).
Kind of wet, with a metallic ring to it :-)
>
>>My original intent was to build a three-stage amp using a
>>choke-loaded driver with a simple gain stage in front, producing
>>full gain without a preamp (tall order).
>
>Well, I do have a Preamp (because I listen to Vinyl - a direct-Input Amp
>is good if Seedee is your main source, but if it is Vinyl a Pre/Power
>solution seems better to me). This will easily do 2-3V into 10k, so no
>Gain-Problems here....
Yes, no problem, your options are much better. I think I was really
setting a tough goal for myself, but I've chosen to go it without a preamp.
>
>As I'm slowly reving up for my 211 Stereo Amp project, I'm really
>intersted in this thread. I have narrowed down my choice of Driver to
>two possible Topologies:
>
>1) Ongaku
>
>2) Ciro Marzio's Orpheo in a Version 1.5 sort of (417A into 2A3 choke
>loaded - fixed bias into 211 fixed Bias)
>
>Either version will use a Choke Input Filter PSU for +B though (kinda
>scary though at +1250V +B......)......
>
>I'm not sure, but I might end up using 211's as Rectifiers too....
>
>>Even more interesting was a fixed-bias 6A5G.
>
>What is that one? 6A5G? Is that a 6V Filament Version?
The 6A5G is an indirectly heated version of the 6B4G, sort of. It has tiny
cathode sleeves over the filaments, and operates quietly, which saves a
torturous filament supply. OTOH, the cathodes are center-tapped to the
filaments, so a floating supply is necessary unless fixed-bias is used of
course. They cost about the same as a NOS 6B4G or a new 6B4G, for that
matter.
My best results were gotten with a choke-input supply for the output tube
(VV52) with fixed bias, and a separate choke-input supply for the
choke-loaded 6A5G, also with fixed bias. A paralleled 12AU7 or something
similar in front sounded just lovely, but that's up for grabs.
My "consultants" were a bit surprised when I expressed dissatisfaction with
this version, as the sound was quite good (gee, that doesn't sound so
humble, does it?), but when I shared the results of the CF on my system
(see below) the reason for changing became clear. Not a step forward,
really, just a move in another direction which got me closer to what I was
looking for, all things considered.
I have not tried the 10, which certainly has all the goods to make an
excellent driver, except for the highish Rp, but that shouldn't be a
problem with suitable inductance on the plate. But then there's that DC
filament supply :-( (see below).
>>*sound*--
>
>Now that is the interesting bit....
>
>Then of course there is the Question of which source you are using....
My main source is CDs, which poses a challenge in and of itself :-). I
have a professionally modified Harmon Kardon which is capable of extreme
clarity and very intense musical expression. I've heard the player under
numerous circumstances and have a pretty clear idea of its capabilities,
and wanted to bring out the best in it with my amp.
I also use ProAc Response 2s, which I find irreplaceable until I hear
something better. And most of my collection consists of full-scale
orchestral music. So bear in mind that extreme delicacy of expression was
not a major factor, as it might be with Lowthers or horns. Of course I
wanted grace and refinement, but more important was power and control, but
without forcing the music. Again, this came into play with directly-heated
drivers, in terms of the quality of the filament supply. Any of the DC
supplies I tried either wrecked the tone of the tube or diminished its
ability to convey speed and clarity. Someone of your experience should be
able to solve this problem, but for me it started to look a bit
overwhelming. Hopefully I'll go back at some point and revisit this issue.
That's the past six months in a nutshell.
Grover Gardner
groverg@postoffice.att.net
=========================================================================
From: Paul Joppa <pdj@ISDNseattle.net>
Subject: Re: Cathode follower drive
Date: Mon, 29 Jun 1998 19:11:21 -0700
Source: Sound Digest Archive v01.n328
Grover Gardner wrote:
> As for operating points, I've experienced the opposite. It was only after
> trying something close to the Ongaku operating points, higher Vp and lower
> current, that I've come to like this tube. The Ongaku runs the 5687 CF at
> 250 Vp and about 7 mA, if my calculations are correct.
Grover-
so... what are you using? Vp, Vk, v-, Rk ... America wants to know!!
- -Paul
=========================================================================
From: Grover Gardner <groverg@postoffice.att.net>
Subject: Re: Cathode follower drive
Date: Tue, 30 Jun 1998 00:14:03 -0500
Source: Sound Digest Archive v01.n328
At 7:11 PM -0700 6/29/98, Paul Joppa wrote:
>Grover Gardner wrote:
>> As for operating points, I've experienced the opposite. It was only after
>> trying something close to the Ongaku operating points, higher Vp and lower
>> current, that I've come to like this tube. The Ongaku runs the 5687 CF at
>> 250 Vp and about 7 mA, if my calculations are correct.
>
>Grover-
>
>so... what are you using? Vp, Vk, v-, Rk ... America wants to know!!
It does, huh? :-) Well, it's all junk box stuff right now, paralleled
whatsits to get approximate values and I'm still playing with the operating
points, but...
The main B+ is 400 volts, with a VV52 biased at -75 for 120mA. Dropping
resistor is 27K with decoupling cap to 5687 CF plate for 150 volts. The
load resistor on the cathode is 11K and the negative voltage is -195 from a
diode-rectified, choke-filtered supply. So we're dropping 120 volts across
the resistor, that's 11mA current. There's a bias pot from the negative
supply to feed the grid of the CF for setting the CF grid bias, thus
adjusting the VV52 bias.
What I've found so far: increase the load (15K) and drop the current (8mA)
and it gets real soft and sweet. Drop the load and increase the current
and it gets a bit sturdier and tougher-sounding. As you'd expect, I
suppose. I'm flying in the dark, have to look more into issues of loading
and proper voltage swing, but so far it seems to be doing the job, and with
a decent load and 225 volts across the tube, I guess I'm safe for the time
being. Paul, care to enlighten me as to how well it's actually working or
not? How high should the load be to ensure good linear swing?
The gain stage is a cap-coupled 5687 running at about the same place, 230
Vp with a 13K resistor, 1K cathode resistor unbypassed for 10-12 mA, with a
cap-coupled parallel 12AT7 in front of that.
I tried the "totem pole" config with the 12AT7, better than SRPP but still
didn't really care for it. I'm not dismissing it, just didn't spend a lot
of time with it and prefer the parallel plate follower for now.
Johari hit the nail on the head--with all three stages paralleled the sound
was mighty intense--"under pressure" is a good way to put it. All three
with single stages and it gets too soft and sweet for me. Season to taste,
I guess! Maybe I'll compromise and parallel the first two stages but leave
the CF alone.
OTOH, I stopped at Tower tonight and got Blind Willie McTell's last session
on Prestige and Dick Wellstood "Live at the Sticky Wicket". They sound so
damn good I oughta just leave it alone, fer cripes' sake!
Grover Gardner
groverg@postoffice.att.net
=========================================================================
From: "T. Loesch" <ezee_e@hotmail.com>
Subject: Re: Cathode follower drive
Date: Tue, 30 Jun 1998 02:46:40 PDT
Source: Sound Digest Archive v01.n328
Hi Grover and all,
>>>Oh, I've choke-loaded everything from a 2A3 to the kitchen sink
>>>:-).
>>How did the Kitchen Sink sound with that? Dynamic and Three
>>Dimensional ;-).
>Kind of wet, with a metallic ring to it :-)
Yuck. Better not do that again....
>My best results were gotten with a choke-input supply for the output
>tube (VV52) with fixed bias, and a separate choke-input supply for
>the choke-loaded 6A5G, also with fixed bias. A paralleled 12AU7
>or something similar in front sounded just lovely, but that's up
>for grabs.
Sounds to me like the way to go then.... And Yes, I will use a seperate
Choke Input Supply for the Frontend....
>My "consultants" were a bit surprised when I expressed
>dissatisfaction with this version, as the sound was quite good
>(gee, that doesn't sound so humble, does it?), but when I shared
>the results of the CF on my system (see below) the reason for
>changing became clear. Not a step forward, really, just a move
>in another direction which got me closer to what I was
>looking for, all things considered.
This is interesting/good to know.... I think some of this is also system
and taste related....
>My main source is CDs, which poses a challenge in and of itself :-).
Yes indeed. As I posted before, I have tested my modded Marantz against
one of the better DAC's in this world (the Audio-Synthesis DAX), one
which is a lot better than the Parts Connection DAC with Upgrade Kit and
I found the hotrodded Marantz to give VERY little to the DAX (HDCD
Filter, Ultra Analog DAC's, Discrete Output Stages, three massive
toroidal X-Formers and various bits of shielding all over the Place -
very nice DAC).
At the same time, even im my current System my analog Rig makes
listening to Seedees almost a chore....
>I have a professionally modified Harmon Kardon which is capable
>of extreme clarity and very intense musical expression. I've heard
>the player under numerous circumstances and have a pretty clear
>idea of its capabilities, and wanted to bring out the best in it with
>my amp.
Ah well, My system gets optimised for Vinyl.... Seedees make up maybe
10% of my Music Collection, probably less....
>I also use ProAc Response 2s, which I find irreplaceable until I hear
>something better.
Try the Big ProAc (Response 5) or a Wilson Audio Watt 3/ Puppy 2 with a
newer Tweeter retrofitted.... Else try Quad ESL's with the Gradient
Subwoofer.... ;-)
However the Response 2s is quite a nice Speaker....
> Again, this came into play with directly-heated drivers, in terms of
>the quality of the filament supply. Any of the DC supplies I tried
>either wrecked the tone of the tube or diminished its
>ability to convey speed and clarity.
Hmmm. What sort of Fillament Arrangements did you try?
I intend to use 2200 uF Elna Starget (the Top of the Line Cerafines and
a lot cheaper than Black Gate) from each side of the Cathode to Ground,
with a fully symmetrical Fillament Supply (+/-3V) applied to these Cap's
through a common mode Choke (probably about 2 X 0.5H or so....).
Regulators before the Choke....
A similar Arrangement is planned for the 211....
>That's the past six months in a nutshell.
Thank you very much again for sharing your findings.... It seems I will
go the DHT Driver route, probably with the Sovtek 6B4G....
For my taste and system preferences I think that will provide the better
solution....
Now to aquire the Iron and start building the PSU without Electrocuting
myself....
Kind regards Thorsten.
======================================
e-mail:
Thorsten@tnt-audio.com
Visit TNT-Audio on the Web - the only advertising
free audio web-zine.
http://www.tnt-audio.com
======================================
______________________________________________________
Get Your Private, Free Email at http://www.hotmail.com
=========================================================================
From: "Johari Yip" <hfyip@pacific.net.sg>
Subject: Re: Cathode follower drive
Date: Tue, 30 Jun 1998 08:43:42 +0800
Source: Sound Digest Archive v01.n328
- ----------
> From: Grover Gardner <groverg@postoffice.att.net>
> To: Johari Yip <hfyip@pacific.net.sg>; 'sound@mail.tpoint.net'
<sound@deliverator.io.com>
> Subject: Re: Cathode follower drive
> Date: Monday, June 29, 1998 11:35 PM
> Interestingly, this weekend I tried paralleling all sections--12AT7, 5687
> and 5687 CF. The difference was pretty shocking--extreme, almost
> frightening clarity, an incredibly potent, powerful sound. In fact,
really
> too much, I thought. Not very relaxing to listen to, but certainly
> revealing!
Grover
That's exactly my experience too. Paralleling the 2 sections improves the
forcefulness of the presentation, more transparent but then again it's like
listening to the music under a bit of "pressure" (if this is the right word
for it). I guess there's something to do with the internal impedance of the
tube being reduced and not to mention, less tube noise too. Still, I prefer
this setup.
Johari
=========================================================================
From: Thomas Dunker <dunker@invalid.ed.unit.no>
Subject: Re: Cathode follower drive
Date: Tue, 30 Jun 1998 15:28:48 +0200 (MET DST)
Source: Sound Digest Archive v01.n328
On Tue, 30 Jun 1998, Johari Yip wrote:
> ----------
> > From: Grover Gardner <groverg@postoffice.att.net>
> > To: Johari Yip <hfyip@pacific.net.sg>; 'sound@mail.tpoint.net'
> <sound@deliverator.io.com>
> > Subject: Re: Cathode follower drive
> > Date: Monday, June 29, 1998 11:35 PM
>
> > Interestingly, this weekend I tried paralleling all sections--12AT7, 5687
> > and 5687 CF. The difference was pretty shocking--extreme, almost
> > frightening clarity, an incredibly potent, powerful sound. In fact,
> really
> > too much, I thought. Not very relaxing to listen to, but certainly
> > revealing!
>
> Grover
>
> That's exactly my experience too. Paralleling the 2 sections improves the
> forcefulness of the presentation, more transparent but then again it's like
> listening to the music under a bit of "pressure" (if this is the right word
> for it). I guess there's something to do with the internal impedance of the
> tube being reduced and not to mention, less tube noise too. Still, I prefer
> this setup.
Why don't you guys just look for triodes with the qualities one would
want in a cathode follower tube: high gm, high plate voltages (for
a driver stage) or use a constant voltage thing in the plate circuit like
Allen Wright recommends. I personally think a lot of the prejudice
against CFs is based on poorly designed CFs using suboptimal
tubes(12AT/AU/AX7 etc.), but I guess you knew that already... I use one
section of a 6BL7GTA as the top tube of a White Cathode Follower in my SE
801 amps, with a pentode constant current source (6SG7) - this makes up for
the lowish gm of the 6BL7 in terms of output impedance and allows me to
get plenty of A2 power out of the 801.
At constant current the output Z of a cathode follower is approximately
1/gm.
Some miniature tubes have high max plate dissipation and high gm,
such as the 7119/E182CC and could be run at high voltage/high current
for these kinds of jobs. There's also a bunch of nice pentodes that
turn into high-gm wonder-triodes when triode wired, one example being the
7788/E810F that Grego mentioned in his SP article. Another is the 7722/
E280F, which takes 4W of plate dissipation and provides a gm of 33mA/V
at 24mA/160V on the plate. And is VERY linear. The pentode that smokes
them all is the E55L/8233, with amazing linearity when triode wired
(much like a WE437A or 3A/167M) and a gm of 50mA/V, a mu of 30 and an ri
of 600 ohms at 55.5mA/125V on the plate. This tube is apparently happiest
at high current/low voltage, but is rated for a max plate dissipation
of 10W and a screen dissipation of 1.5W, and Torbjoern told me just
yesterday thet he's wound two output transformers specifically for
tubes like E55L and 3A/167M. The tubes could still be used for killer
cathode followers.
Check out the "The Search For Linearity" articles in GA for more on
improved CFs.
Torbjoern Lien (temporarily off line due to dead computer) suggests
one more trick to improve the cathode follower, as he suggests that
cathode-filament capacitance modulated by the signal can cause
ugly side effects: Apply the signal to both halves of a twin triode
(let's call them A and B) and use the signal at the cathode of B
to bias the (floating) heater supply of the tube, use the signal
at the cathode of A as the output signal. This way the heater-
cathode potential remains constant and any sort of signal
correlated leakage effects would be reduced to a minimum. I will
try this in my new line stage soon.
Tom D.
- -------------------------------------------------------------------------
_/\_ Thomas Dunker \ The Horn Speaker Home Page:
/ \ P.O.Box 2811 \ http://invalid.ed.ntnu.no/~dunker/horns.html
| | 7002 Trondheim \
| | NORWAY \--\ "Those with head above water
\____/ dunker@omegav.ntnu.no \ see only the tip of the iceberg"
|||| phone (+47)73916898 \ (Gene Dalby)
- ------------------------------------------------------------------------
=========================================================================
From: "T. Loesch" <ezee_e@hotmail.com>
Subject: Re: Cathode follower drive
Date: Tue, 30 Jun 1998 08:11:04 PDT
Source: Sound Digest Archive v01.n329
Hi there,
>or use a constant voltage thing in the plate circuit like Allen
>Wright recommends.
I tried that in my Preamp's Linestage. I tried AW's "Super Linear
Cathode Follower" (sic), SRPP and simple Common Cathode Stage with
paralleled halves. With a 6DJ8.
In the End the Common Cathode Stage geve the best results....
But then, I don't drive more than 200pF....
>There's also a bunch of nice pentodes that turn into high-gm
>wonder-triodes when triode wired, one example being the
>7788/E810F that Grego mentioned in his SP article.
Has anyone actually got a Data-Sheet around for the E810F? I have a few
in my Valves Box....
Kind regards Thorsten.
======================================
e-mail:
Thorsten@tnt-audio.com
Visit TNT-Audio on the Web - the only advertising
free audio web-zine.
http://www.tnt-audio.com
======================================
______________________________________________________
Get Your Private, Free Email at http://www.hotmail.com
=========================================================================
From: CERREM <merrec@mail1.jpl.nasa.gov>
Subject: Re: Cathode follower drive
Date: Tue, 30 Jun 1998 16:49:21 -0700
Source: Sound Digest Archive v01.n329
>
Paralleling the sections does reduce noise allowing more subtle tones to be
unmasked... Since this also lowers the source Z in half.... the frequency
reponse is extended in the output driving capabilities... Thus giving better
phase response at the top of the audio band..
Also parallel operation of valves doubles the transconductance ( "input
sensitivity")
...therefore giving rise to more musical detail and "jump factor"..
Remember that when biasing a follower...it is the difference between plate
and grid.... This is also the Max driving signal to apply in class A1...
Also note that the output resistance of follower is the source resistance in
parallel with the cathode resistor.....
A good way to visual see a follwers operating point or to calculate a
operating point..is to redraw over the family of plate curves...with cathode
curves....... then plot the loads..
CHEERS
CM
>
> ----------
> > From: Grover Gardner <groverg@postoffice.att.net>
> > To: Johari Yip <hfyip@pacific.net.sg>; 'sound@mail.tpoint.net'
> <sound@deliverator.io.com>
> > Subject: Re: Cathode follower drive
> > Date: Monday, June 29, 1998 11:35 PM
>
> > Interestingly, this weekend I tried paralleling all sections--12AT7, 5687
> > and 5687 CF. The difference was pretty shocking--extreme, almost
> > frightening clarity, an incredibly potent, powerful sound. In fact,
> really
> > too much, I thought. Not very relaxing to listen to, but certainly
> > revealing!
>
> Grover
>
> That's exactly my experience too. Paralleling the 2 sections improves the
> forcefulness of the presentation, more transparent but then again it's like
> listening to the music under a bit of "pressure" (if this is the right word
> for it). I guess there's something to do with the internal impedance of the
> tube being reduced and not to mention, less tube noise too. Still, I prefer
> this setup.
>
> Johari
=========================================================================
From: Paul Joppa <pdj@ISDNseattle.net>
Subject: Re: Cathode follower drive
Date: Tue, 30 Jun 1998 21:29:33 -0700
Source: Sound Digest Archive v01.n329
Grover Gardner wrote:
>
> The main B+ is 400 volts, with a VV52 biased at -75 for 120mA. Dropping
> resistor is 27K with decoupling cap to 5687 CF plate for 150 volts. The
> load resistor on the cathode is 11K and the negative voltage is -195 from a
> diode-rectified, choke-filtered supply. So we're dropping 120 volts across
> the resistor, that's 11mA current. There's a bias pot from the negative
> supply to feed the grid of the CF for setting the CF grid bias, thus
> adjusting the VV52 bias.
>
> What I've found so far: increase the load (15K) and drop the current (8mA)
> and it gets real soft and sweet. Drop the load and increase the current
> and it gets a bit sturdier and tougher-sounding. As you'd expect, I
> suppose. I'm flying in the dark, have to look more into issues of loading
> and proper voltage swing, but so far it seems to be doing the job, and with
> a decent load and 225 volts across the tube, I guess I'm safe for the time
> being. Paul, care to enlighten me as to how well it's actually working or
> not? How high should the load be to ensure good linear swing?
Dunno about "light" - I think there's more going on than any theory I
can come up with will explain (note my complex explanation for Doc's
simple problem...) 225v at 11mA is very close to one of the book
values. It's already pretty tall & thin, Eb/Ib of about 7 rp. (The
other book value, 180v/23mA/2k rp, is closer to 4; I like about 5).
From the book values (I don't have any curves available) it is clear
that the nonlinear region (non-parallel grid curves) extends up to
this tall/thin operating point - the mu drops from 17 to 16, and the
plate resistance increases more than the current ratio to the 1/3
power. So I think you are increasing the distortion by going to lower
current. It's quite possible that this is simply cancelling distortion
in another stage (the other half of the 5687?) so more may be less(!)
Both stages are operating at the same output level so would have
similar distortion, though the CF feedback will reduce its distortion.
I note that the Ongaku runs only 50v peak drive from 150v across the
cathode load (33%) while you are running 75v drive from 120v on the
resistor (63%) - that will double the 2nd and increase higher
harmonics even more.
So there's in theory a distortion effect. I'm not saying that's the
only thing going on, however!
- -Paul Joppa
=========================================================================
From: Grover Gardner <groverg@postoffice.att.net>
Subject: Re: Cathode follower drive
Date: Tue, 30 Jun 1998 22:59:11 -0500
Source: Sound Digest Archive v01.n329
At 4:49 PM -0700 6/30/98, CERREM wrote:
>>
>
> Paralleling the sections does reduce noise allowing more subtle tones to be
>unmasked... Since this also lowers the source Z in half.... the frequency
>reponse is extended in the output driving capabilities... Thus giving better
>phase response at the top of the audio band..
>Also parallel operation of valves doubles the transconductance ( "input
>sensitivity")
>...therefore giving rise to more musical detail and "jump factor"..
>Remember that when biasing a follower...it is the difference between plate
>and grid.... This is also the Max driving signal to apply in class A1...
>Also note that the output resistance of follower is the source resistance in
>parallel with the cathode resistor.....
>A good way to visual see a follwers operating point or to calculate a
>operating point..is to redraw over the family of plate curves...with cathode
>curves....... then plot the loads..
Thanks for the notes. Obviously I have a lot to learn about cathode
followers :-). I spoke to friend today who suggested that the load be much
larger than what I am using, and to increase the top and bottom voltages to
ensure I get the swing I need to drive the output tubes. He said as much
as 400 volts across the tube, if necessary. I asked about maximum plate
voltages and current and he said "no, no, it's a cathode follower..." and
then his kid fell down the steps or something and he had to hang up. He's
a busy man anyway and I hate to take up too much of his time so I see I
have my work cut out for me in the study department :-). In the meantime
I'll keep fiddling with it.
What do you mean, CM, by "the difference between the plate and the grid"?
I won't ask how to draw a set of cathode curves, unless you have all day--I
can probably figure it out.
Grover Gardner
groverg@postoffice.att.net
=========================================================================
From: "Johari Yip" <hfyip@pacific.net.sg>
Subject: Re: Cathode follower drive
Date: Wed, 1 Jul 1998 09:32:25 +0800
Source: Sound Digest Archive v01.n329
- ----------
> From: T. Loesch <ezee_e@hotmail.com>
> To: hfyip@pacific.net.sg; dunker@invalid.ed.unit.no
> Cc: sound@deliverator.io.com; groverg@postoffice.att.net
> Subject: Re: Cathode follower drive
> Date: Tuesday, June 30, 1998 11:11 PM
> >There's also a bunch of nice pentodes that turn into high-gm
> >wonder-triodes when triode wired, one example being the
> >7788/E810F that Grego mentioned in his SP article.
>
> Has anyone actually got a Data-Sheet around for the E810F? I have a few
> in my Valves Box....
Should it be E180F instead of E810F? (great tube to use for a single tube
phono stage too).
Johari
=========================================================================
From: CERREM <merrec@mail1.jpl.nasa.gov>
Subject: Re: Cathode follower drive
Date: Wed, 01 Jul 1998 11:02:02 -0700
Source: Sound Digest Archive v01.n329
Grover Gardner wrote:
> At 4:49 PM -0700 6/30/98, CERREM wrote:
> >>
> >
> > Paralleling the sections does reduce noise allowing more subtle tones to be
> >unmasked... Since this also lowers the source Z in half.... the frequency
> >reponse is extended in the output driving capabilities... Thus giving better
> >phase response at the top of the audio band..
> >Also parallel operation of valves doubles the transconductance ( "input
> >sensitivity")
> >...therefore giving rise to more musical detail and "jump factor"..
> >Remember that when biasing a follower...it is the difference between plate
> >and grid.... This is also the Max driving signal to apply in class A1...
> >Also note that the output resistance of follower is the source resistance in
> >parallel with the cathode resistor.....
> >A good way to visual see a follwers operating point or to calculate a
> >operating point..is to redraw over the family of plate curves...with cathode
> >curves....... then plot the loads..
>
> Thanks for the notes. Obviously I have a lot to learn about cathode
> followers :-). I spoke to friend today who suggested that the load be much
> larger than what I am using, and to increase the top and bottom voltages to
> ensure I get the swing I need to drive the output tubes. He said as much
> as 400 volts across the tube, if necessary. I asked about maximum plate
> voltages and current and he said "no, no, it's a cathode follower..." and
> then his kid fell down the steps or something and he had to hang up. He's
> a busy man anyway and I hate to take up too much of his time so I see I
> have my work cut out for me in the study department :-). In the meantime
> I'll keep fiddling with it.
>
> What do you mean, CM, by "the difference between the plate and the grid"?
> I won't ask how to draw a set of cathode curves, unless you have all day--I
> can probably figure it out.
>
> Grover Gardner
> groverg@postoffice.att.net
I have no problem with helping explain something that may be helpfull to
you.....I will explain how to draw the cathode curves from the plate
curves...next email...
But for now view it this way.... Lets say you have a valve with a 100K plate
resistor
and is use as a traditional common cathode amp....Then the bias would be the
difference between grid and cathode...this is also the Max. signal level for
input for class A1....
Now for cathode follower......at same operating point...simply remove 100K from
plate and put it in the cathode instead..... now turn the schematic upside
down....the plate is returned to ground via de-coupling cap... The new biasing
point is now the difference between the plate voltage and grid voltage.....this
is also max input voltage drive for class A1.........Cathode followers can take
mush bigger input signals than their common-cathode counterparts...
The same operating point also can be a cathadyne phase inverter.....break the
100K in half..and put 50K in plate and 50K in cathode (47K as in
Williamson)...still same operating point...but now the plate is not fully
bypassed to ground ..thus increased feedback and less gain than follower...
A Cathode follower can't be whipped up by "try this and try that" ....Trial
and error.....
It must be designed properly for a given situation.... you must have knowledge
of what it is it needs to drive and at what frequency response you want.....then
it's duck soup after that..
CHEERS
CM
=========================================================================
From: An-shyang Chu <achu@sandia.gov>
Subject: Re[2]: Cathode follower drive
Date: 01 Jul 1998 13:26:05 -0600
Source: Sound Digest Archive v01.n329
Hi Grover, CM (Creeem?) and JC,
Does this means that the slopes of the I-V plate cureves doubled when you
parallel tubes... i.e. with the same bias point only half of the current is
needed for each sections? I am trying to think, but my head keeps on spinning
due to a bad cool (5-days in the counting).
Best regards,
hopper
_______________________________________________________________________________
Subject: Re: Cathode follower drive
From: groverg@postoffice.att.net at hubsmtp
Date: 6/30/98 9:23 PM
At 4:49 PM -0700 6/30/98, CERREM wrote:
>>
>
> Paralleling the sections does reduce noise allowing more subtle tones to be
>unmasked... Since this also lowers the source Z in half.... the frequency
>reponse is extended in the output driving capabilities... Thus giving better
>phase response at the top of the audio band..
>Also parallel operation of valves doubles the transconductance ( "input
>sensitivity")
>...therefore giving rise to more musical detail and "jump factor"..
>Remember that when biasing a follower...it is the difference between plate
>and grid.... This is also the Max driving signal to apply in class A1...
>Also note that the output resistance of follower is the source resistance in
>parallel with the cathode resistor.....
>A good way to visual see a follwers operating point or to calculate a
>operating point..is to redraw over the family of plate curves...with cathode
>curves....... then plot the loads..
Thanks for the notes. Obviously I have a lot to learn about cathode
followers :-). I spoke to friend today who suggested that the load be much
larger than what I am using, and to increase the top and bottom voltages to
ensure I get the swing I need to drive the output tubes. He said as much
as 400 volts across the tube, if necessary. I asked about maximum plate
voltages and current and he said "no, no, it's a cathode follower..." and
then his kid fell down the steps or something and he had to hang up. He's
a busy man anyway and I hate to take up too much of his time so I see I
have my work cut out for me in the study department :-). In the meantime
I'll keep fiddling with it.
What do you mean, CM, by "the difference between the plate and the grid"?
I won't ask how to draw a set of cathode curves, unless you have all day--I
can probably figure it out.
Grover Gardner
groverg@postoffice.att.net
=========================================================================
From: Grover Gardner <groverg@postoffice.att.net>
Subject: Re: Cathode follower drive
Date: Wed, 1 Jul 1998 14:49:54 -0500
Source: Sound Digest Archive v01.n329
At 11:02 AM -0700 7/1/98, CERREM wrote:
> I have no problem with helping explain something that may be helpfull to
>you.....I will explain how to draw the cathode curves from the plate
>curves...next email...
>But for now view it this way....
etc.
Oh, gosh, this seems very clear! So if I have 170 volts on the plate, -12
on the grid and -80 on the cathode, the tube is operating at 250 volts, and
I have 182 volts of potential headroom for the previous stage.
I am a fearless experimenter but very poor at conceptualizing how circuits
work. Flipping the thing upside down makes it much easier to understand.
I can't thank you enough, this is far more info than I had before. I
eagerly await more when you have the time.
Grover Gardner
groverg@postoffice.att.net
=========================================================================
From: Grover Gardner <groverg@postoffice.att.net>
Subject: Re: Cathode follower drive
Date: Wed, 1 Jul 1998 16:21:26 -0500
Source: Sound Digest Archive v01.n329
At 3:28 PM +0200 6/30/98, Thomas Dunker wrote:
> Why don't you guys just look for triodes with the qualities one would
>want in a cathode follower tube: high gm, high plate voltages (for
>a driver stage) or use a constant voltage thing in the plate circuit like
>Allen Wright recommends. I personally think a lot of the prejudice
>against CFs is based on poorly designed CFs using suboptimal
>tubes(12AT/AU/AX7 etc.), but I guess you knew that already... I use one
>section of a 6BL7GTA as the top tube of a White Cathode Follower in my SE
>801 amps, with a pentode constant current source (6SG7) - this makes up for
>the lowish gm of the 6BL7 in terms of output impedance and allows me to
>get plenty of A2 power out of the 801.
> At constant current the output Z of a cathode follower is approximately
>1/gm.
> Some miniature tubes have high max plate dissipation and high gm,
>such as the 7119/E182CC and could be run at high voltage/high current
>for these kinds of jobs. There's also a bunch of nice pentodes that
>turn into high-gm wonder-triodes when triode wired, one example being the
>7788/E810F that Grego mentioned in his SP article. Another is the 7722/
>E280F, which takes 4W of plate dissipation and provides a gm of 33mA/V
>at 24mA/160V on the plate. And is VERY linear. The pentode that smokes
>them all is the E55L/8233, with amazing linearity when triode wired
>(much like a WE437A or 3A/167M) and a gm of 50mA/V, a mu of 30 and an ri
>of 600 ohms at 55.5mA/125V on the plate. This tube is apparently happiest
>at high current/low voltage, but is rated for a max plate dissipation
>of 10W and a screen dissipation of 1.5W, and Torbjoern told me just
>yesterday thet he's wound two output transformers specifically for
>tubes like E55L and 3A/167M. The tubes could still be used for killer
>cathode followers.
Yes, the 8233 is a spectacular tube--know someone who uses these in a
preamp and phono stage. Too bad they're almost $40US each...:-)
>
> Check out the "The Search For Linearity" articles in GA for more on
>improved CFs.
> Torbjoern Lien (temporarily off line due to dead computer) suggests
>one more trick to improve the cathode follower, as he suggests that
>cathode-filament capacitance modulated by the signal can cause
>ugly side effects: Apply the signal to both halves of a twin triode
>(let's call them A and B) and use the signal at the cathode of B
>to bias the (floating) heater supply of the tube, use the signal
>at the cathode of A as the output signal. This way the heater-
>cathode potential remains constant and any sort of signal
>correlated leakage effects would be reduced to a minimum. I will
>try this in my new line stage soon.
That's interesting! Hmmmmm......
Grover Gardner
groverg@postoffice.att.net
=========================================================================
From: Thomas Dunker <dunker@invalid.ed.unit.no>
Subject: Re: Cathode follower drive
Date: Wed, 1 Jul 1998 21:51:21 +0200 (MET DST)
Source: Sound Digest Archive v01.n329
On Wed, 1 Jul 1998, Grover Gardner wrote:
> Yes, the 8233 is a spectacular tube--know someone who uses these in a
> preamp and phono stage.
Interesting. Got the circuit diagrams?
> > Too bad they're almost $40US each...:-)
Glad I have 7 NOS Mullards! I also have a fairly large quantity
of a tube type that would be equally weird/interesting in a high
gain preamp, a tube I haven't seen ANYONE refer to ANYWHERE. It's
an STC/ITT triode called 3B/240M, a power VHF repeater tube (20 watts
max plate dissipation) with a loctal base. It sports a mu of 90
and a transconductance of 27 mA/V, and that's about all the info
I have on it. It's also a strong candidate for a one stage SE power
amp, but its internal impedance works out to be in the neighborhood of
3k. I have no idea of its linearity though. If anyone has a detailed
STC tube manual with info on this tube, please let me know.
Tom D.
- -------------------------------------------------------------------------
_/\_ Thomas Dunker \ The Horn Speaker Home Page:
/ \ P.O.Box 2811 \ http://invalid.ed.ntnu.no/~dunker/horns.html
| | 7002 Trondheim \
| | NORWAY \--\ "Those with head above water
\____/ dunker@omegav.ntnu.no \ see only the tip of the iceberg"
|||| phone (+47)73916898 \ (Gene Dalby)
- ------------------------------------------------------------------------
=========================================================================
From: CERREM <merrec@mail1.jpl.nasa.gov>
Subject: Re: Cathode follower drive
Date: Wed, 01 Jul 1998 14:47:29 -0700
Source: Sound Digest Archive v01.n330
Grover Gardner wrote:
> At 11:02 AM -0700 7/1/98, CERREM wrote:
>
> > I have no problem with helping explain something that may be helpfull to
> >you.....I will explain how to draw the cathode curves from the plate
> >curves...next email...
> >But for now view it this way....
>
> etc.
>
> Oh, gosh, this seems very clear! So if I have 170 volts on the plate, -12
> on the grid and -80 on the cathode, the tube is operating at 250 volts, and
> I have 182 volts of potential headroom for the previous stage.
>
> I am a fearless experimenter but very poor at conceptualizing how circuits
> work. Flipping the thing upside down makes it much easier to understand.
>
> I can't thank you enough, this is far more info than I had before. I
> eagerly await more when you have the time.
>
> Grover Gardner
> groverg@postoffice.att.net
With cathode follower...forget about the grid to cathode voltage... Just like
when doing common cathode circuits..when do you ever hear someone making
reference to the plate to cathode voltage?????? Well with cathode followers
it's upside down....your only concerned with two numbers..the plate to cathode
voltage and the plate to grid voltage wiich is the biasing point.... remember
that with common cathode the input signal is applied between grid and
cathode....With followers , the input signal is appied between grid and
plate....since plate is returned to ground via de-couplin cap.... Here is
deal with cathode curves.....for the fearless experimenter... :)
Just get the plate curves...and subtract the plate volts by the grid
volts....
For ex: Starting at the 0 grid bias curve..... you then choose a arbitrary
voltage like 100V on the plate voltage ...then visualy go straight up and
intersect the 0 bias curve....Now start drawing a line going down going
towards the left by increments of bias ...meaning that as you intersect the
- -2 bias line you should be at (100-2) 98 volts ........ as you intersect the
- -5 curve you should be at (100-5) 95 volts...and so forth till
cut-off......this single curve would be labled -100 .......cathode curve.
When drawing a cathode curve in a region of the plate curves where there is no
available 0 bias curve simply start at whatever bias curve is available
....for example.... choosing 300V go up to the smallest bias available for
example..lets say it's -8...... now simply start at (300-8) 292v when
intersecting the -8 bias curve and then when intersecting the -10 curve you
should be at (300-10) 290 volts..... this would be the -300 cathode curve...
You carry this out for a bunch of voltages until you get as many as
needed......
Now you can plot a load line and properly set the voltage swing as
needed...as well as see the operating current..... To figure the aproximate
output impedance of the follower ..simply put the source resistance in
parallel with the cathode resistor.....
The source resistance is the slope of the operating curve you are biased
at.....since these cathode curves are very steep and straight.....just divide
(delta E / delta I) for a small linear length of the curve near the
quiscient point ....
For practice...try backwards engineering a popular circuit with cathode
follower.... making sure the measured voltages agree with the math and curve
calculations to some reasonable degree..... When you can do that...then
figure the math calculations for the Macintosh MC-30 direct coupled cathode
follwer (12AX7).... this includes bootstrapping of positive feedback.. Hint:
the biasing circuit is a bit tricky with summing of multible currents in
different directions...
CHEERS
CM
=========================================================================
From: Grover Gardner <groverg@postoffice.att.net>
Subject: Re: Cathode follower drive
Date: Thu, 2 Jul 1998 00:22:50 -0500
Source: Sound Digest Archive v01.n330
At 8:53 AM +0800 7/2/98, Johari Yip wrote:
>----------
>> From: Thomas Dunker <dunker@invalid.ed.unit.no>
>> To: Grover Gardner <groverg@postoffice.att.net>
>> Cc: Johari Yip <hfyip@pacific.net.sg>; 'sound@mail.tpoint.net'
><sound@deliverator.io.com>
>> Subject: Re: Cathode follower drive
>> Date: Thursday, July 02, 1998 3:51 AM
>>
>> On Wed, 1 Jul 1998, Grover Gardner wrote:
>>
>> > Yes, the 8233 is a spectacular tube--know someone who uses these in a
>> > preamp and phono stage.
>>
>> Interesting. Got the circuit diagrams?
>
>I'm interested in the schematics too. BTW, the schematics I have is a
>phonostage taken from a website (sorry, can't recall what's the URL) using
>a single E180F. I suspect it's only
>good for MM because it's loaded at 47K at the input. Anyone interested.
I wish I did know the circuit. It's a commercial design so I've never
ventured to ask. The phonostage is for moving coil, using all triode-wired
pentodes and no step-up tranny. It's the quietest, most transparent thing
I've ever heard. Unfortunately it isn't cheap, either--a bit steep for me.
If you have a big audio budget and want to hear the best phono stage I've
ever had the pleasure of hearing, drop me a line :-) I'm sure it can be
done by others, but my friend has some very good experience working with
high Gm tubes and does some very clever things with them.
As for the CF, I've been getting that sorted out and am not far off the
mark, I think. Thanks to CM for his very helpful post, which I don't think
got reporduced in full, at least his first one. He suggested a way of
visualizing the CF which made the critical elements a lot clearer to me.
Carter Hendricks is going to fax me some material tomorrow as well. We
were talking on the phone tonight and wondering how either of us could ever
have built anything at all without help from this terrific community.
Carter and I were also talking about CFs and I wanted mention that for a
test I did a little re-wiring and dropped a 12BH7 in place of the 5687 CF,
since it can be run about the same. I see where this "flatness" issue
comes in--the 12BH7 didn't convey nearly the spacial info and roundedness
of the 5687 or 7044. Again, I suppose you could work with it but a simple
A-B seemed convincing that the 5687 has more to offer.
Grover Gardner
groverg@postoffice.att.net
=========================================================================
From: "Johari Yip" <hfyip@pacific.net.sg>
Subject: Re: Cathode follower drive
Date: Thu, 2 Jul 1998 08:53:11 +0800
Source: Sound Digest Archive v01.n330
- ----------
> From: Thomas Dunker <dunker@invalid.ed.unit.no>
> To: Grover Gardner <groverg@postoffice.att.net>
> Cc: Johari Yip <hfyip@pacific.net.sg>; 'sound@mail.tpoint.net'
<sound@deliverator.io.com>
> Subject: Re: Cathode follower drive
> Date: Thursday, July 02, 1998 3:51 AM
>
> On Wed, 1 Jul 1998, Grover Gardner wrote:
>
> > Yes, the 8233 is a spectacular tube--know someone who uses these in a
> > preamp and phono stage.
>
> Interesting. Got the circuit diagrams?
I'm interested in the schematics too. BTW, the schematics I have is a
phonostage taken from a website (sorry, can't recall what's the URL) using
a single E180F. I suspect it's only
good for MM because it's loaded at 47K at the input. Anyone interested.
Johari
=========================================================================
From: Simon Busbridge <S.C.Busbridge@bton.ac.uk>
Subject: Re: cathode followers
Date: Thu, 11 Sep 1997 11:05:11 +0100 (BST)
Source: Sound Digest Archive v01.n019
Guido - here is a personal view!
Like many of us, I too have experimented with several designs of cathode
follower. It's very easy to get terrific detail, but they suffer from a
sterile, two dimensional presentation. I have had the best results when
the CF is linearised by another valve working into a negative supply, but
the same general observations apply.
It's probably a direct consequence of the large amount of feedback
preventing the music from "breathing". I tend to prefer low mu valves in
CF arrangements, because the feedback fraction is smaller. I don't know
if this accounts for my observations with the ECC range - the 83 is the
least musically inspiring in CF, the 81 better and the 82 quite good.
Similarly the 6SN7 sounds quite good. I don't know how even lower mu
valves like the 12B4A would sound.
My latest pre-amp will ditch the CF approach and use a 20:1 line output
transformer from Simon Shilton instead. Having said that, I quite like
my current design with ECC82s - Mullards are giving the best results.
Simon Busbridge
=========================================================================
From: Guido Tent <gtent@ehv.sc.philips.com>
Subject: cathode followers
Date: Thu, 11 Sep 1997 11:11:05 +0200
Source: Sound Digest Archive v01.n019
Hi all,
Maybe not the first to introduce the cathode follower and it's (sonical) merrits
Any of you experienced ?
I have implemented CFs in lots of designs, and allthough I am very far in
improving their sound, I still do not like them completely. They seem to
have (to keep) a kind of "mechanical"sound, which I cannot get rid of
What is wrong with a cathode follower ? How can we ommit the merrits and
make them sound right ?
Guido
" 640K ought to be enough for anybody" , Bill Gates, 1981
Disclaimer: The opinions expressed herin are my personal ones and do not in
any way reflect opinions or policies of my employer.
Guido Tent
Engineer Electro Magnetic Compatibility
Philips Semiconductors Systems Laboratory Eindhoven (PS-SLE)
Building BE303, (Hurksestraat 19)
P.O.Box 218, 5600MD Eindhoven, The Netherlands
Phone: +31-40-27 24553
fax : +31-40-27 22764
- - Let's make things better ! -
E-mail: guido.tent@ehv. sc.philips.com
Seri : gtent@nlsce1
=========================================================================
From: "Daniel J. Marshall" <danmarshall@worldnet.att.net>
Subject: Re: cathode followers
Date: Sun, 14 Sep 1997 08:08:15 -0700
Source: Sound Digest Archive v01.n022
Hugh R. Dean wrote:
>
> Hi Simon, you wrote:
>
> >It's probably a direct consequence of the large amount of feedback
> >preventing the music from "breathing". I tend to prefer low mu valves in
> >CF arrangements, because the feedback fraction is smaller. I don't know
> >if this accounts for my observations with the ECC range - the 83 is the
> >least musically inspiring in CF, the 81 better and the 82 quite good.
> >Similarly the 6SN7 sounds quite good. I don't know how even lower mu
> >valves like the 12B4A would sound.
>
> I wonder about the feedback too, which is 100% voltage and guilty of
> macerating music in SS and tube amps alike. However, I'd be interested in
> your notion that the feedback factor is smaller with low mu tubes.
>
> If it's any surprise, David O'Rourke, who writes for Glass Harmony and a
> couple of years back produced a very interesting 15W PP triode design using
> 212As believes that the best tube in CF mode is the 12B4A. Frankly, I
> can't see too many other reasons for ultra low mu tubes but transformers
> and CFs!
>
> On another subject, I am presently experimenting with a 1:1 IT at 6mA in
> the plate circuit of a 12AU7. I have 125V on the top of the IT primary,
> filtered through a triple RC filter, with maybe 1mV of 100Hz ripple on the
> B+, and having a real problem with hum. Although I am only swinging about
> 30Vpp on the IT, I have noticed the IT is very sensitive to hum fields from
> the mains tranny.
>
> What is the best shielding and or trick to stop ITs from humming? It's
> driving me mad!
>
> Cheers,
>
> Hugh R. Dean
> Melbourne, Australia
Hugh,
For the hum problem try the old trick used in TV sets. This consists
placing a low impedance shorted turn around the entire core of the power
transformer to short out the stray magnetic fields. This forces the
stray hum fields to travel through the now lower reluctance path through
the core as originally intended. This shorting strap should be a piece
of copper sheet, as thick as you can easily work with and the width of
the windings. It should be placed around the entire core oriented in
the direction of the windings and overlapped about a quarter of an inch,
or so, and securely soldered. Winding turns of magnet wire is not as
effective, but can pinch hit for the strap, at least for a test, if
heavy gauge wire is used and the turns are soldered across at one point
with a blob of solder to create a single turn. Multiple turns will have
too much inductance. This does not make a very attractive mod, but if
copper sheeting is not readily available, you can use heavy gauge wire
for a test, and, if it does the job, get some copper strap for a
permanent mod. The strap can be placed under the end bells and the
solder joint under the chassis for an acceptable appearanmce. Some
power transformers are supplied with this strap.
With regard to the feedback issue discussed above, I wonder about the
theory postulated, as the problem with massive amounts of feedback, as I
perceive it, is primarily due to deficiencies in output transformers. I
can see how massive amounts of feedback can cause problems when the
higher order harmonics in the feedback signal get out of phase with the
input signal, thereby adding thereto (multiplying?), rather than
decreasing harmonic distortions, and causing crossmodulations within the
audible band, etc. However, I cannot envision this occurring in a
properly designed cathode follower circuit. Cathode followers (CF) and
emitter followers (EF) can be unstable and indeed can oscillate, at
least in the SS versions. So, any time a CF or EF is used its stability
should be verified by sweeping it up to a very high frequency and
observing its gain response with a wideband oscilloscope. Any peaking
in the higher frequencies is indicative of potential stability problems
which may manifest itself as parasitic oscillations (which likely will
be dependent somewhat on temperature and external shielding such as
bottom plate covers, etc.) and may exaggerate higher order distortions
which perhaps could be related to the postulated feedback deficiencies
referred to above. Notice I said "perhaps", I am not making any
dogmatic pronouncements here. Tubes with higher transconductance would
be more likely to exhibit high frequency instabilities, however, I do
not suggest that avoiding them would be the proper solution, rather, I
would think higher gm would be preferred, assuming the circuit is
unconditionally stable, i. e., does not exhibit any high frequency
peaking. I haven't played about with CF circuits in a very long time,
but have had quite a bit of experience with EFs in wideband video
amplifiers. It is not advisable to drive an EF from a low source
impedance and I suspect this (and other factors) may be the case with
CFs as well. Many times I have had to modify commercial equipment to
tame an oscillating EF. This is generally accomplished by installing a
270 ohm, or so, resistor in series with the base. Since I have not
messed about with CF circuits in many decades, I will not venture to
propose a satisfactory soultion. Although, as I see it, it is a very
simple problem to test on the bench and remedy. I have had many years
of bench experience in years gone by and can generally get right to the
heart of most circuit deficiencies and remedy them fairly quickly.
Also, it is important to provide a current source in the cathode leg for
CFs and this is more important with lower gm tubes, as they tend to
follow the signal less faithfully. A current source can be the form of
a pentode, a FET, or a large value resistor supplied by a fairly high
negative voltage source. If a current source is not used, the circuit
becomes very dependent upon the tube linearity, so it may be that
conclusions have been erroneously drawn which are based upon indirectly
related factors.
Dan Marshall
=========================================================================
From: "Hugh R. Dean" <aspen@alphalink.com.au>
Subject: Re: cathode followers
Date: Sun, 14 Sep 1997 18:39:36
Source: Sound Digest Archive v01.n022
Hi Simon, you wrote:
>It's probably a direct consequence of the large amount of feedback
>preventing the music from "breathing". I tend to prefer low mu valves in
>CF arrangements, because the feedback fraction is smaller. I don't know
>if this accounts for my observations with the ECC range - the 83 is the
>least musically inspiring in CF, the 81 better and the 82 quite good.
>Similarly the 6SN7 sounds quite good. I don't know how even lower mu
>valves like the 12B4A would sound.
I wonder about the feedback too, which is 100% voltage and guilty of
macerating music in SS and tube amps alike. However, I'd be interested in
your notion that the feedback factor is smaller with low mu tubes.
If it's any surprise, David O'Rourke, who writes for Glass Harmony and a
couple of years back produced a very interesting 15W PP triode design using
212As believes that the best tube in CF mode is the 12B4A. Frankly, I
can't see too many other reasons for ultra low mu tubes but transformers
and CFs!
On another subject, I am presently experimenting with a 1:1 IT at 6mA in
the plate circuit of a 12AU7. I have 125V on the top of the IT primary,
filtered through a triple RC filter, with maybe 1mV of 100Hz ripple on the
B+, and having a real problem with hum. Although I am only swinging about
30Vpp on the IT, I have noticed the IT is very sensitive to hum fields from
the mains tranny.
What is the best shielding and or trick to stop ITs from humming? It's
driving me mad!
Cheers,
Hugh R. Dean
Melbourne, Australia
=========================================================================
From: jc morrison <jc@underline.net>
Subject: Re: cathode followers
Date: Sun, 14 Sep 1997 18:10:40 -0400
Source: Sound Digest Archive v01.n023
dan marshall said:
- - "With regard to the feedback issue discussed above, I wonder about the
theory postulated, as the problem with massive amounts of feedback, as I
perceive it, is primarily due to deficiencies in output transformers. I
can see how massive amounts of feedback can cause problems when the
higher order harmonics in the feedback signal get out of phase with the
input signal, thereby adding thereto (multiplying?), rather than
decreasing harmonic distortions, and causing crossmodulations within the
audible band, etc. However, I cannot envision this occurring in a
properly designed cathode follower circuit."-
good post. actually, the key words here are "properly designed". dan ends
with:
- -"Also, it is important to provide a current source in the cathode leg for
CFs and this is more important with lower gm tubes, as they tend to
follow the signal less faithfully. A current source can be the form of
a pentode, a FET, or a large value resistor supplied by a fairly high
negative voltage source. If a current source is not used, the circuit
becomes very dependent upon the tube linearity, so it may be that
conclusions have been erroneously drawn which are based upon indirectly
related factors."-
this has been my experience as well. the 12B4, as an example, is not very
linear and unless operated constant current tends to significantly distort
the lower half of the wave-form (towards cut-off) on medium to large
swings. even with a CCS, large signal values require sufficient B+ and B-
so as to avoid the really curved range of the tubes characteristics. i know
this from designing a driver stage with it. ended up using a 6CG7 instead.
for a preamp or line driver, the 12B4 has promise however, the very low
output impedance it can offer and the small swing required fits its
capabilities pretty well. i do think that the gain issue is not really much
of a factor with tube CF's. transconductance is everything! getting it
stable is also important, like any stage. in any case, dan's observations
mirror my own, if this is of any use to anyone....
jc
=========================================================================
From: andre@indigo.ie (Andre Jute)
Subject: Re: cathode followers
Date: Sun, 14 Sep 1997 23:48:10 +0100 (BST)
Source: Sound Digest Archive v01.n023
Hugh
>On another subject, I am presently experimenting with a 1:1 IT at 6mA in
>the plate circuit of a 12AU7. I have 125V on the top of the IT primary,
>filtered through a triple RC filter, with maybe 1mV of 100Hz ripple on the
>B+, and having a real problem with hum. Although I am only swinging about
>30Vpp on the IT, I have noticed the IT is very sensitive to hum fields from
>the mains tranny.
>
>What is the best shielding and or trick to stop ITs from humming? It's
>driving me mad!
I'd be interested to hear if the tranny tames the waffle of 12AU7.
Have you shielded the valve itself? An old ham told me that sometimes makes
a difference, because the tube itself picks up hum and amplifies it. He
used steel pipes open at the top with the bottom welded to a collar for
bolting to the chassis, the whole thing polished and black-chromed.
In my two IT linestage amp I simply moved the ITs to the diagonally
opposite corner of a (rather crowded) 17x10in chassis. Also *rotated them
in the third axis* to bolt them to the side rather than the largest face of
the box. Puts them nearer the OPT but that seems to matter less.
(Stephen's interesting reply goes further, simultaneous yaw, pitch and roll
in three dimensions!) Also, all the other the corresponding trannies on
this dual mono back are bolted back to back through quarter-inch ali for (I
hope) stray magnetics cancellation. Finally, in one proto I used the two
mains trannies, bolted back to back as above, in series, and this is the
quietest amp of the lot.
Have you loaded all the secondary windings of your tranny? Per Lundahl's
transformers are specifically so designed that if all the outputs are
loaded, stray magnetic fields are reduced to a minimum. I tested this by
leaving a spare 4A fil winding (otherwise used in parallel just to load it)
open and hum increased a little though I had to get my tube millivolt meter
out to see the diff. I imagine that other kinds of symmetric main trannies
will offer at least some of the same advantage. And Stephen made a
symmetric tranny by running two in series...
Andre
Alas, all the things you cannot learn from books!
Andre Jute
andre@indigo.ie
Communication Jute
the main index to the pages we support for lovers of classical music, for
writers, and for audiophiles is at
http://www.foundmark.com/ComJute/ComJuteF1.html
=========================================================================
From: Guido Tent <gtent@ehv.sc.philips.com>
Subject: Re: cathode followers
Date: Mon, 15 Sep 1997 10:14:15 +0200
Source: Sound Digest Archive v01.n024
At 18:39 14-09-97, you wrote:
>Hi Simon, you wrote:
>
>>It's probably a direct consequence of the large amount of feedback
>>preventing the music from "breathing". I tend to prefer low mu valves in
>>CF arrangements, because the feedback fraction is smaller. I don't know
>>if this accounts for my observations with the ECC range - the 83 is the
>>least musically inspiring in CF, the 81 better and the 82 quite good.
>>Similarly the 6SN7 sounds quite good. I don't know how even lower mu
>>valves like the 12B4A would sound.
I think one should also take a tube with a flat slope to current characteristic
>I wonder about the feedback too, which is 100% voltage and guilty of
>macerating music in SS and tube amps alike. However, I'd be interested in
>your notion that the feedback factor is smaller with low mu tubes.
>
>If it's any surprise, David O'Rourke, who writes for Glass Harmony and a
>couple of years back produced a very interesting 15W PP triode design using
>212As believes that the best tube in CF mode is the 12B4A. Frankly, I
>can't see too many other reasons for ultra low mu tubes but transformers
>and CFs!
>
>On another subject, I am presently experimenting with a 1:1 IT at 6mA in
>the plate circuit of a 12AU7. I have 125V on the top of the IT primary,
>filtered through a triple RC filter, with maybe 1mV of 100Hz ripple on the
>B+, and having a real problem with hum. Although I am only swinging about
>30Vpp on the IT, I have noticed the IT is very sensitive to hum fields from
>the mains tranny.
Becasue it's leaking, its air-gapped
>What is the best shielding and or trick to stop ITs from humming? It's
>driving me mad!
First you have to be sure that th IT is your hum-source. Your amp should be
quiet if you short-circuit the secondary of your IT. Shielding at 50 Hz is
only possible with high mu metal (expensive), so you can kill better the
coupling to the IT by looking for the correct orientation wrt the OTX and
MTX. If you do so your amp will be virtually quiet
Have fun
Guido
>Cheers,
>
>Hugh R. Dean
>Melbourne, Australia
>
>
>
>
" 640K ought to be enough for anybody" , Bill Gates, 1981
Disclaimer: The opinions expressed herin are my personal ones and do not in
any way reflect opinions or policies of my employer.
Guido Tent
Engineer Electro Magnetic Compatibility
Philips Semiconductors Systems Laboratory Eindhoven (PS-SLE)
Building BE303, (Hurksestraat 19)
P.O.Box 218, 5600MD Eindhoven, The Netherlands
Phone: +31-40-27 24553
fax : +31-40-27 22764
- - Let's make things better ! -
E-mail: guido.tent@ehv. sc.philips.com
Seri : gtent@nlsce1
=========================================================================
From: Chris Galbraith <chrisg@ducker.com>
Subject: Cathode follower ?s
Date: Sun, 2 Nov 1997 21:17:22 -0500
Source: Sound Digest Archive v01.n098
Gang,
I'm working on a 50s ham transmitter (the "other" love!) and would like
to try a cathode follower to drive a pair of AB2 807s.
I've never implemented a CF before--this seems like a perfect
application!
Here's what I've come up with so far...
According to the Audio Cyclopedia, Rp (load resistor) is determined by:
Rp=Z x rp / rp - Z(1+u), where:
Rp=load resistor
rp=plate resistance of the tube
Z=output impedance
u=gain of tube
So, I've calculated the following for 3 different tubes:
12AX7 - 20Kohm, Z=600ohms
6CG7 - 7.7Kohm, Z=350ohms
12BH7 - 1.4Kohms, Z=250ohms
My question is, which output Z/tube would be best suited for this
application? 12BH7 would give the lowest Zout, so that appears to be
the best choice.
Next, how do I calculate the output cap's value? I need a LF cutoff of
only ~100hz or so.
What else am I missing here?! Thanks for any input!
- -Chris
=========================================================================
From: "=?ISO-8859-1?Q?Torbj=F8rn_Lien?=" <mdrivekl@online.no>
Subject: Re: Cathode Followers.
Date: Thu, 30 Jul 1998 01:02:18 +0200
Source: Sound Digest Archive v01.n365
YYYYyyiiiiiiHah!!!
Yessss!! It woyks!!! Finally, after nearly 2 mnths, some
lazy repairman managed to fix up this crappy shit-PC
with a new ,-,-(!)... eh,- : something ... and,-of
cource, with all the,-...tubosterone(?) I've accumulated during this
time, I'll simply bite! (Although I should know
better...)
Manfred Huber wrote,
T. Loesch replied:,:
>> Most people I know agree that the simple resistance loaded >> CF
sounds bad.
And why is that?? I don't think so. My experiences with
them ain't so many, but I find them quite useable..I simply
cannot see any reason that they should mess sound up, other than shaky
implementation of the circuit, or with the use of unsuitable lo-gm
tubes...
>> The proposed solution to this problem is to use a current >> sink
in the cathode of the CF. This way the CF tube >> operates at constant
current and the gain of the cf >> approaches 1 (at least when using a
high-mu tube).
>>
> Indeed. And Allen Wright essentially Cascodes the Valve
> for the CF aswell, as a result keeping the Voltage across >the Valve
Constant....
Yeah,- Of cource this all works, but it is seldom nescessary
IMHO. A resistive loaded voltage amp has current swing when
operated, so why shouldn't one allow the CF to do some "work"
aswell,-....Just think of it: If you use, say a E182CC as a
CF output stage in a line amp, typical operating voltages
/current seems "fixed" compared to the lowish output voltage/current
swing...the distortion should be practically nil..
>> BUT this is only true if you don t load the output of the
>> CF. When loading the CF the load resistance is effectively >> in
parallel with the current sink and lowers the impedance >> the cathode
is working into.
>>
> Correct. As soon as the CF sees any significant load it all > goes
out of the Window....
Ehm, yes(?),-..As the plate resistance in a common cathode amp is in
parallell with the following grid resistance +miller-cap.etc. in the
next tube in a cascaded amp... Of course one have to see, and evaluate
the *whole* loading of
a cathodefollower, as any other type of amp...
>> My somewhat provokant question is:
>> What is the use of a low impedance stage that may not >>be
loaded?
>
> 28 Ohm Output Impedance looks good on a Spec-Sheet
> and will appeal to the crowd using unrolled Capacitors as
>interconnects....
A cathodefollower can surely do some work,-(and 28 ohm *is*
28 ohm...)But IMHO most(?) diy'ers seems to think that the low output
impedance equals *current* capability....
(If you use an underrated tube, loafing along with lowish current, you
cant drive much,-now, I would say that that is
a design flaw, rather than a circuit limitation...
>
>>[snip]
Then evaguido wrote :[snipped]
>I found that a resistor (100 ohm to 1 k-ohm) in series with >the anode
of the cathode follower improves the sound as >well. Do not yet know
wh, any of you ?
My guess is selve-oscillations way up in the Mhz or higher range.(It
can be extremely difficult to detect.)It's easy to forget that the
gain-bandwith product in a cathodefollower,
and especially with high gm-tubes, might give small but *big*
trouble...A small resistance in the anode, a suitable gridstopper etc.
will usually supress these tendensies..
I'll finish with some of my own thoughts...Rationally, I
picture this: An "Ideal" powersupply with zero noise, Z or
whatever...Hanging on these "perfect" rails, a tube. Now,
we can reference the whole thing to the outside world as we like, and
put loads in the anode and/or the cathode, and use it as we like....
Now, as this circuit is a "circle", (starting with:>minus
pole PSU,>kathodeload>[tube]anodeload pluspole PSU,
and then back.) I s i m p l y c a n n o t s e e
why one side (the current amp side) means disaster to sound,
while the other side (the voltage amp side) means heaven...
Can someone explain this?
.....Meaning we have to investigate other properties of an actual
real-world circuit.........
I think the "nearness" (and "randomlike" coupling) to the filament
might cause some grunge, that is more or less "hidden" by the low
output Z of the cathodefollower..There are a number of leakage
components between the cathode and filament; capasitive coupling,
leakage current and resistance,(semiconductor action?), paths into the
(noisy parts)of a PSU and back..These components are not linear, but
temperature - type - brand -etc. dependent aswell.
(I don't know much of these mechanisms, but I bet thei're
able to create some subtle evilness..)
In short: The cathode is not in "free space" like the anode.
But then, why not try to emulate this, if we're using the
cathode as a signal out: Treat the tube in a cathode follower as you
would a direct heated one, with a *low* noise filament
supply..make this supply *truly* floating with minimal stray
components to the outside world.Then, it can be connected
directly to the cathode,and there will be *no* varying components
between it and the filament..Or, why not hook the filament (+ supply )
directly to a similar, but dedicated
"filament-floater-kathodefollower..The idea is that two separate
followers is driven by the same signal: One is used for signal out
only, the other swings the common filament in perfect phase and
amplitude with the output signal...That should make the "signal
out-cathode" reasonably "free-floating" I guess..
Anyone care to try this out?
Oops, getting late :(
Bye for now,
:)TL
=========================================================================
From: Michael Kerster <MKers@idirect.com>
Subject: Re: Cathode Followers.
Date: Wed, 29 Jul 1998 22:52:51 -0400
Source: Sound Digest Archive v01.n366
Hey Joes,
Where is Norman Crowhurst when you need him? In my own experience, Cathode
followers should only be used into a "bridging" load ie., the impedance
that the cathode follower is "looking into"
should be at least 10X the AC source impedance. In asfar as active loads
are concerned, they
alter very little the AC loadline, while maintaining the desired DC
current. Resistor loaded cathode followers can have variable sound quality,
depending on the "recieve" impedance. Keep
in mind that the rise and fall times of a resistor loaded cathode follower
are definately not equal, and the active load mitigates this to some
degree. I personally prefer med mu, high current tiodes ie., 1/2 6DN7,
6FM7, 6BL/BX7. This, of course IMHO.
iAt 01:02 AM 7/30/98 +0200, Torbjørn Lien wrote:
>YYYYyyiiiiiiHah!!!
>
>Yessss!! It woyks!!! Finally, after nearly 2 mnths, some
>lazy repairman managed to fix up this crappy shit-PC
>with a new ,-,-(!)... eh,- : something ... and,-of
>cource, with all the,-...tubosterone(?) I've accumulated during this
>time, I'll simply bite! (Although I should know
>better...)
>
>Manfred Huber wrote,
>T. Loesch replied:,:
>
>>> Most people I know agree that the simple resistance loaded >> CF
>sounds bad.
>
>And why is that?? I don't think so. My experiences with
>them ain't so many, but I find them quite useable..I simply
>cannot see any reason that they should mess sound up, other than shaky
>implementation of the circuit, or with the use of unsuitable lo-gm
>tubes...
>
>>> The proposed solution to this problem is to use a current >> sink
>in the cathode of the CF. This way the CF tube >> operates at constant
>current and the gain of the cf >> approaches 1 (at least when using a
>high-mu tube).
>>>
>> Indeed. And Allen Wright essentially Cascodes the Valve
>> for the CF aswell, as a result keeping the Voltage across >the Valve
>Constant....
>
>Yeah,- Of cource this all works, but it is seldom nescessary
>IMHO. A resistive loaded voltage amp has current swing when
>operated, so why shouldn't one allow the CF to do some "work"
>aswell,-....Just think of it: If you use, say a E182CC as a
>CF output stage in a line amp, typical operating voltages
>/current seems "fixed" compared to the lowish output voltage/current
>swing...the distortion should be practically nil..
>
>>> BUT this is only true if you don t load the output of the
>>> CF. When loading the CF the load resistance is effectively >> in
>parallel with the current sink and lowers the impedance >> the cathode
>is working into.
>>>
>> Correct. As soon as the CF sees any significant load it all > goes
>out of the Window....
>
>Ehm, yes(?),-..As the plate resistance in a common cathode amp is in
>parallell with the following grid resistance +miller-cap.etc. in the
>next tube in a cascaded amp... Of course one have to see, and evaluate
>the *whole* loading of
>a cathodefollower, as any other type of amp...
>
>>> My somewhat provokant question is:
>>> What is the use of a low impedance stage that may not >>be
>loaded?
>>
>> 28 Ohm Output Impedance looks good on a Spec-Sheet
>> and will appeal to the crowd using unrolled Capacitors as
>>interconnects....
>
>A cathodefollower can surely do some work,-(and 28 ohm *is*
>28 ohm...)But IMHO most(?) diy'ers seems to think that the low output
>impedance equals *current* capability....
>(If you use an underrated tube, loafing along with lowish current, you
>cant drive much,-now, I would say that that is
>a design flaw, rather than a circuit limitation...
>>
>>>[snip]
>
>Then evaguido wrote :[snipped]
>
>>I found that a resistor (100 ohm to 1 k-ohm) in series with >the anode
>of the cathode follower improves the sound as >well. Do not yet know
>wh, any of you ?
>
>My guess is selve-oscillations way up in the Mhz or higher range.(It
>can be extremely difficult to detect.)It's easy to forget that the
>gain-bandwith product in a cathodefollower,
>and especially with high gm-tubes, might give small but *big*
>trouble...A small resistance in the anode, a suitable gridstopper etc.
>will usually supress these tendensies..
>
>I'll finish with some of my own thoughts...Rationally, I
>picture this: An "Ideal" powersupply with zero noise, Z or
>whatever...Hanging on these "perfect" rails, a tube. Now,
>we can reference the whole thing to the outside world as we like, and
>put loads in the anode and/or the cathode, and use it as we like....
>Now, as this circuit is a "circle", (starting with:>minus
>pole PSU,>kathodeload>[tube]anodeload pluspole PSU,
>and then back.) I s i m p l y c a n n o t s e e
>why one side (the current amp side) means disaster to sound,
>while the other side (the voltage amp side) means heaven...
>Can someone explain this?
>
>.....Meaning we have to investigate other properties of an actual
>real-world circuit.........
>
>I think the "nearness" (and "randomlike" coupling) to the filament
>might cause some grunge, that is more or less "hidden" by the low
>output Z of the cathodefollower..There are a number of leakage
>components between the cathode and filament; capasitive coupling,
>leakage current and resistance,(semiconductor action?), paths into the
>(noisy parts)of a PSU and back..These components are not linear, but
>temperature - type - brand -etc. dependent aswell.
>(I don't know much of these mechanisms, but I bet thei're
>able to create some subtle evilness..)
>
>In short: The cathode is not in "free space" like the anode.
>But then, why not try to emulate this, if we're using the
>cathode as a signal out: Treat the tube in a cathode follower as you
>would a direct heated one, with a *low* noise filament
>supply..make this supply *truly* floating with minimal stray
>components to the outside world.Then, it can be connected
>directly to the cathode,and there will be *no* varying components
>between it and the filament..Or, why not hook the filament (+ supply )
>directly to a similar, but dedicated
>"filament-floater-kathodefollower..The idea is that two separate
>followers is driven by the same signal: One is used for signal out
>only, the other swings the common filament in perfect phase and
>amplitude with the output signal...That should make the "signal
>out-cathode" reasonably "free-floating" I guess..
>
>Anyone care to try this out?
>
>Oops, getting late :(
>Bye for now,
>
>:)TL
>
=========================================================================
From: "Le Cleac'h J.-M." <lecleach@cgi.ensmp.fr>
Subject: Re: Cathode Followers.
Date: Thu, 30 Jul 1998 09:17:12 +0200
Source: Sound Digest Archive v01.n366
Hello,
To add some juice at the discussion I was wondering how can a same person
denigrate resistively loaded CF and highly favor unbypassed cathod
resistor?
NFB witgh both...
Best regards,
Jean-Michel Le Cleac'h, Paris, France
=========================================================================
From: jc morrison <jcm@eclipse.net>
Subject: Cathode Followers
Date: Thu, 30 Jul 1998 10:28:18 -0700
Source: Sound Digest Archive v01.n367
finn wrote:
> This offer is too good to be true, so I`l jump in here, eager to learn
> something.
>
> I have the tubes, a regulated supply, scope, signal generator and
> multimeters. A tape recorder for signal source, and will have to drag a
> speaker into the basement workshop.
> Let`s do it! On the net.
>
> I`l make a little breadboard, what next?
>
> Finn
and manfred wrote:
(start)
My last experience with a CF was like this:
I tried to use a direct coupled CF as the last stage of a RIAA amp
because of it s low input impedance. It was a 6021 submin triode
(rp=6k5 mu=35 gm=5400). The anode current was about 5mA and the cathode
resistor was 27K. All the stage had to drive was a 100K pot in the same
chassis coupled to the CF by a 1uF cap. While this did not sound bad at
all the sound improved when I was substituting a current sink for the
27K resistor thereby bringing the effective load resistance up from
21k (27k parallel to 100k) to roughly 100K. As the impedance seen when
looking into the cathode was only about 200 Ohms in this case one should
think that a change in the load from 27K to 100K should not make much
difference. As I see it there are two possibilities: Either my design of
the CF was flawed (possible) or the CF does not want to be loaded for a
reason I can t explain.
(end)
first of all, manfred, please don't take any of this critically! this is
an opportunity to get to the bottom of "something", and perhaps there is
someone who will benefit from a discussion like this? your experience
above is a great starting point, and "flawed" is way too strong of a
word for the situation... we could ask first, "why did the sound
change?" answering this might be pretty useful, right? and finn is
enthusiastically waiting to strike with his hot soldering iron...
1) i was thinking about worst case examples and i came up with two
separate nasty loading tests: an electric motor (AC) and a large
capacitor (how about 20uf).
2) what do we test? a good thing to do would be to breadboard a circuit
where one could quickly change the cathode load: resistor/choke/current
source. a variable power supply, two of them actually, so we can provide
varying amounts across plate and cathode circuits.
3) there are two common practical situations where one might apply a
cathode follower: line voltages where isolation and loading are issues
(small swings into a variable load), and driving a power triode grid
(large swings into a variable load). we might want to know how our
breadboarded circuit does with these particular tasks and what are the
differences if any???
4) can you think of anything else related to this test that might help
you?
finn, a question for you... do you use auto cad? i don't have the
patience for ascii schematics, can't read em anyway. i can email
attached .dxf files....
jc
=========================================================================
From: evaguido <EvaGuido@iaehv.nl>
Subject: Re: Cathode Followers.
Date: Thu, 30 Jul 1998 18:43:40 +0200
Source: Sound Digest Archive v01.n367
At 01:02 30-7-98 +0200, Torbjørn Lien wrote:
>YYYYyyiiiiiiHah!!!
>
>Yessss!! It woyks!!! Finally, after nearly 2 mnths, some
>lazy repairman managed to fix up this crappy shit-PC
>with a new ,-,-(!)... eh,- : something ... and,-of
>cource, with all the,-...tubosterone(?) I've accumulated during this
>time, I'll simply bite! (Although I should know
>better...)
Congratulations and welcome
>Manfred Huber wrote,
>T. Loesch replied:,:
>
>>> Most people I know agree that the simple resistance loaded >> CF
>sounds bad.
>
>And why is that?? I don't think so.
I do, CF:
- - have 2 inputs, the grid and the cathode (since both voltages can
influence the current)
- -have 100 % feedback (since gain is about unity)
This looks like an operational amplifier, in follower mode, or not ?
Circuits like these give odd harmonics !
The problem is independant of the voltage swing
The chosen valve should have flat s as function of current and high mu if
possible
Have fun
Guido
>My experiences with
>them ain't so many, but I find them quite useable..I simply
>cannot see any reason that they should mess sound up, other than shaky
>implementation of the circuit, or with the use of unsuitable lo-gm
>tubes...
>
>>> The proposed solution to this problem is to use a current >> sink
>in the cathode of the CF. This way the CF tube >> operates at constant
>current and the gain of the cf >> approaches 1 (at least when using a
>high-mu tube).
>>>
>> Indeed. And Allen Wright essentially Cascodes the Valve
>> for the CF aswell, as a result keeping the Voltage across >the Valve
>Constant....
>
>Yeah,- Of cource this all works, but it is seldom nescessary
>IMHO. A resistive loaded voltage amp has current swing when
>operated, so why shouldn't one allow the CF to do some "work"
>aswell,-....Just think of it: If you use, say a E182CC as a
>CF output stage in a line amp, typical operating voltages
>/current seems "fixed" compared to the lowish output voltage/current
>swing...the distortion should be practically nil..
>
>>> BUT this is only true if you don t load the output of the
>>> CF. When loading the CF the load resistance is effectively >> in
>parallel with the current sink and lowers the impedance >> the cathode
>is working into.
>>>
>> Correct. As soon as the CF sees any significant load it all > goes
>out of the Window....
>
>Ehm, yes(?),-..As the plate resistance in a common cathode amp is in
>parallell with the following grid resistance +miller-cap.etc. in the
>next tube in a cascaded amp... Of course one have to see, and evaluate
>the *whole* loading of
>a cathodefollower, as any other type of amp...
>
>>> My somewhat provokant question is:
>>> What is the use of a low impedance stage that may not >>be
>loaded?
>>
>> 28 Ohm Output Impedance looks good on a Spec-Sheet
>> and will appeal to the crowd using unrolled Capacitors as
>>interconnects....
>
>A cathodefollower can surely do some work,-(and 28 ohm *is*
>28 ohm...)But IMHO most(?) diy'ers seems to think that the low output
>impedance equals *current* capability....
>(If you use an underrated tube, loafing along with lowish current, you
>cant drive much,-now, I would say that that is
>a design flaw, rather than a circuit limitation...
>>
>>>[snip]
>
>Then evaguido wrote :[snipped]
>
>>I found that a resistor (100 ohm to 1 k-ohm) in series with >the anode
>of the cathode follower improves the sound as >well. Do not yet know
>wh, any of you ?
>
>My guess is selve-oscillations way up in the Mhz or higher range.(It
>can be extremely difficult to detect.)It's easy to forget that the
>gain-bandwith product in a cathodefollower,
>and especially with high gm-tubes, might give small but *big*
>trouble...A small resistance in the anode, a suitable gridstopper etc.
>will usually supress these tendensies..
>
>I'll finish with some of my own thoughts...Rationally, I
>picture this: An "Ideal" powersupply with zero noise, Z or
>whatever...Hanging on these "perfect" rails, a tube. Now,
>we can reference the whole thing to the outside world as we like, and
>put loads in the anode and/or the cathode, and use it as we like....
>Now, as this circuit is a "circle", (starting with:>minus
>pole PSU,>kathodeload>[tube]anodeload pluspole PSU,
>and then back.) I s i m p l y c a n n o t s e e
>why one side (the current amp side) means disaster to sound,
>while the other side (the voltage amp side) means heaven...
>Can someone explain this?
>
>.....Meaning we have to investigate other properties of an actual
>real-world circuit.........
>
>I think the "nearness" (and "randomlike" coupling) to the filament
>might cause some grunge, that is more or less "hidden" by the low
>output Z of the cathodefollower..There are a number of leakage
>components between the cathode and filament; capasitive coupling,
>leakage current and resistance,(semiconductor action?), paths into the
>(noisy parts)of a PSU and back..These components are not linear, but
>temperature - type - brand -etc. dependent aswell.
>(I don't know much of these mechanisms, but I bet thei're
>able to create some subtle evilness..)
>
>In short: The cathode is not in "free space" like the anode.
>But then, why not try to emulate this, if we're using the
>cathode as a signal out: Treat the tube in a cathode follower as you
>would a direct heated one, with a *low* noise filament
>supply..make this supply *truly* floating with minimal stray
>components to the outside world.Then, it can be connected
>directly to the cathode,and there will be *no* varying components
>between it and the filament..Or, why not hook the filament (+ supply )
>directly to a similar, but dedicated
>"filament-floater-kathodefollower..The idea is that two separate
>followers is driven by the same signal: One is used for signal out
>only, the other swings the common filament in perfect phase and
>amplitude with the output signal...That should make the "signal
>out-cathode" reasonably "free-floating" I guess..
>
>Anyone care to try this out?
>
>Oops, getting late :(
>Bye for now,
>
>:)TL
>
>
=========================================================================
From: jc morrison <jcm@eclipse.net>
Subject: Re: Cathode Followers
Date: Thu, 30 Jul 1998 15:37:21 -0700
Source: Sound Digest Archive v01.n368
Finn Hammer wrote:
>
finn wrote:
> Will this do?
>
> Finn
>
if thats what you have, it'll do!
jc
=========================================================================
From: MHuber@t-online.de (Manfred Huber)
Subject: Re: Cathode Followers
Date: Thu, 30 Jul 1998 19:16:36 +0100
Source: Sound Digest Archive v01.n368
JC,
>first of all, manfred, please don't take any of this critically!
Be assured that I have no problem with getting advice in public.
>and "flawed" is way too strong of a word for the situation.
Even if you would think my design is a piece of **** you could say so.
(not everyone is allowed to do this, but you are one of my heroes <g>)
>.. we could ask first, "why did the sound change?" answering this
>might be pretty useful, right? and finn is enthusiastically waiting
>to strike with his hot soldering iron...
Is this meant bo be a new kind of torture? I want to know NOW!
ok, I will wait..
>4) can you think of anything else related to this test that might help
>you?
Well, why not play a piece of music through it. I prefere mosfets
for driving ac motors <g>
Best Regards
Manfred
- ------------------
Manfred Huber
MHuber@t-online.de
- ------------------
=========================================================================
From: Finn Hammer <f-hammer@post5.tele.dk>
Subject: Re: Cathode Followers
Date: Thu, 30 Jul 1998 20:25:58 +0200
Source: Sound Digest Archive v01.n368
jc morrison wrote:
bigsnip....
> finn, a question for you... do you use auto cad?
smallsnip....
> jc
Not if I can avoid it, but since this is not an option, I`l get a copy
up and running over the weekend. Keep those .DXF`s coming!
You mentioned 2 supplies, here is what I`ve got:
1 pcs. 0~30v @ 3A
1 pcs. Double 0~30V @10A
1 pcs. 0~500V @ 300mA (& -85~0 @ 5mA + 6.3 V heaters)
Will this do?
Finn
- --
HOME OF
Tractrix Horns, Tube Amps,
Fieldcoil Loudspeakers and Computer Graphics
http://home5.inet.tele.dk/f-hammer/
=========================================================================
From: davidbarnett@aristotle.net (David Barnett)
Subject: Re: Cathode Followers
Date: Thu, 30 Jul 1998 21:06:54 GMT
Source: Sound Digest Archive v01.n368
On Thu, 30 Jul 1998 20:25:58 +0200, Finn Hammer
<f-hammer@post5.tele.dk> wrote:
>Keep those .DXF`s coming!
Please correct me if I'm wrong, but if both users have AutoCAD,
wouldn't you be better off sening .dwg files? Unless I'm mistaken, a
.dwg file will be smaller than a .dxf of the same drawing, no?
- --dnb, AutoCAD R14 dunce
=========================================================================
From: "=?ISO-8859-1?Q?Torbj=F8rn_Lien?=" <mdrivekl@online.no>
Subject: Re: Cathode Followers.
Date: Fri, 31 Jul 1998 01:13:17 +0200
Source: Sound Digest Archive v01.n368
Hi,
Guido wrote:
>I do, CF:
>- have 2 inputs, the grid and the cathode (since both >voltages can
>influence the current)
>-have 100 % feedback (since gain is about unity)
>This looks like an operational amplifier, in follower mode, >or not ?
Well, yes. Looks like.
>Circuits like these give odd harmonics !
Ehm,-I'm not sure what you mean here. But I guess you are
reffering to a change of the spectrum of the residual harmonic
distortion, so that even harmonics some how are
not in proportion to the odd harmonics,-as often seen in balanced/pp
amps. I cant see how *one single* tube can accomplish this.With full
voltage feedback, as in a
single cathodefollover stage, the whole dist.spectrum is evenly
reduced,-atleast in the "working range" of the stage. Of course, near
clipping the odd harmonic now is dominant,- but that is something
different, I think.
>The problem is independant of the voltage swing
? Would you elaborate on this mechanism ? I must confess
a certain confusion here, as I never have actually used
feedback with the reduction of distortion in mind,-
Instead I often uses small doses of local voltage feedback around
single stages (for better, or appropriate impedance-matching to loads),
and to my ears with *no* bad side effects whatsoever...(Oh yes, I
know,- boring, possibly polithically
uncorrect and completely out of fashion,- :)TL
=========================================================================
From: Finn Hammer <f-hammer@post5.tele.dk>
Subject: Re: Cathode Followers
Date: Sun, 02 Aug 1998 22:31:23 +0200
Source: Sound Digest Archive v01.n373
jc morrison wrote:
>
> if thats what you have, it'll do!
> jc
I spent this weekend building a breadboard with 4-pin, octal and 9 pin
sockets. And a panel with schrouded sockets for the connections to the Vreg.
Nothing fancy, just a piece of oriental ply, and probably too small for
comfort.
Also made a set of 10 wires, 0,25 sqmm silicone insulated, and rated at 800
volts, with shrouded pins in each end. I know that one day, I`l leave them
dangling from the supply, live, so in the name of safety....
Also checked all the tubes in the Vreg., which is new to me, and which I had
never hooked up to a load. It needed a fuse somewhere. Changed the Hi-volt
output sockets to schrouded types. Nice Phillips thing from Singer
Electronics in germany (300$, thanks Bodo and Wolfgang !)
Started to play around with some tubes, mainly testing, how much current
they would transmit, and how redhot they would get. :-) 6SN7`s are amazing
in that respect, woulda thought they got red a lot before they did, really.
Installed Autocad V. 13
I`m ready to go, JC, set me straight!
Finn
- --
HOME OF
Tractrix Horns, Tube Amps,
Fieldcoil Loudspeakers and Computer Graphics
http://home5.inet.tele.dk/f-hammer/
=========================================================================
From: evaguido <EvaGuido@iaehv.nl>
Subject: Re: Cathode Followers.
Date: Tue, 11 Aug 1998 16:54:35 +0200
Source: Sound Digest Archive v01.n384
At 01:13 31-7-98 +0200, Torbjørn Lien wrote:
>Hi,
>
>Guido wrote:
>
>>I do, CF:
>
>>- have 2 inputs, the grid and the cathode (since both >voltages can
>>influence the current)
>>-have 100 % feedback (since gain is about unity)
>
>>This looks like an operational amplifier, in follower mode, >or not ?
>
>Well, yes. Looks like.
>
>>Circuits like these give odd harmonics !
>
>Ehm,-I'm not sure what you mean here. But I guess you are
>reffering to a change of the spectrum of the residual harmonic
>distortion, so that even harmonics some how are
>not in proportion to the odd harmonics,-as often seen in balanced/pp
>amps.
Yup, that is what I mean
>I cant see how *one single* tube can accomplish this.
Even this one single tube has two inputs influencing the current. On one of
these inputs (the cathode) full feedback is present, the other is the input
of the stage
>With full
>voltage feedback, as in a
>single cathodefollover stage, the whole dist.spectrum is evenly
>reduced,-atleast in the "working range" of the stage.
No, it is not
>Of course, near
>clipping the odd harmonic now is dominant,- but that is something
>different, I think.
Yes, I don't go there
>>The problem is independant of the voltage swing
>
>? Would you elaborate on this mechanism ? I must confess
>a certain confusion here, as I never have actually used
>feedback with the reduction of distortion in mind,-
As I did (do) :-)
A lower voltage swing gives absolute lower distortion, but relatively the same
Guido
>Instead I often uses small doses of local voltage feedback around
>single stages (for better, or appropriate impedance-matching to loads),
>and to my ears with *no* bad side effects whatsoever...(Oh yes, I
>know,- boring, possibly polithically
>uncorrect and completely out of fashion,- :)TL
=========================================================================
From: "=?ISO-8859-1?Q?Torbj=F8rn_Lien?=" <mdrivekl@online.no>
Subject: Re: Cathode Followers.
Date: Wed, 12 Aug 1998 19:25:16 +0200
Source: Sound Digest Archive v01.n386
Guido,all:
I'm much puzzeled by this,-
Guido wrote:
>I do, CF: have 2 inputs, the grid and the cathode (since >both
voltages can influence the current) -have 100 % >feedback (since gain
is about unity)
>This looks like an operational amplifier, in follower mode, >or not ?
Circuits like these give odd harmonics !
Myselve wrote:
>>Ehm,-I'm not sure what you mean here. But I guess you are
>>reffering to a change of the spectrum of the residual >>harmonic
distortion, so that even harmonics some how are
>>not in proportion to the odd harmonics,-as often seen in
>>balanced/pp amps.
>Yup, that is what I mean
>>I cant see how *one single* tube can accomplish this.
>>With full voltage feedback, as in a single cathodefollover >>stage,
the whole dist.spectrum is evenly reduced,-atleast >>in the "working
range" of the stage.
>No, it is not
>Even this one single tube has two inputs influencing the >current. On
one of these inputs (the cathode) full feedback >is present, the other
is the input of the stage.
>The problem is independant of the voltage swing
[snip]
Sorry, I cant find any sense in this. My point was that a
single triodetube is something *way* different than an OP-
amp.And the point that both circuits have 2 input terminals
makes them in *no* way similar.So I say again: Cathodefollowers does
not introduce exessive, or even
altered odd harmonic distortion.
There are several ways to show this.
As you yourselves pointed out , this is a circuit with 100%
neg. feedback. Now, why should a stage respond to this feed-
back by reducing the even order harmonics more than the
reducing of the odd order harmonics? As distortion is by def.
variation of gain through a cycle ,this gain variation is
reduced by the feedback factor, thus the circuit *can not* differ
between the various components of this distortion,
reducing one type more or less than another type.
Another way is to look at the characteristic curves of any
triode-tube. By noting that *all* triodes to a varying degree shares
these basic characteristics, it is easily seen that
a single triodetube has even harmonics as its most noticeable
nonlinearity. This does *not* change by connecting the tube
as a cathodefollower. Infact, getting a single triode to
amplify (voltage or current) with major odd order distortion is very
difficult, the only way would be to place the working point so that
clipping is perfectly symmetrical, and then run the stage *very* hard.
To find the actual distortion in a cathodefollower, the
easiest way, I guess is to: Take the cathodeload and connect
to the anode, so that you get a normal common cathode stage
with no feedback. Test it with some signals, so that the output voltage
at the anode gets the same working (AC) value (as the cathodefollower
is aimed for.) Take note of the gain,(the Rp) and of the 2. and 3.
harmonic distortion of the stage. Now: The harmonic distortion (and
Rp) is reduced by the gain factor when replacing the load to the
cathode.Both 2. and 3. Theire relative magnitude is unaltered.
This shows infact how valuable local feedback is as a
construction tool, as it is only "shifting" the tubes own's
parameters. Thus, by allowing small doses of local feedback, a slightly
"out of spec." tube might do the trick.Or, if a
circuit ends up with gain to spare, it might be used to something
useful,which usually would be to linearize the
output stage.
:TL
>
>
>
>
=========================================================================
From: evaguido <EvaGuido@iaehv.nl>
Subject: Re: Cathode Followers.
Date: Wed, 12 Aug 1998 19:48:30 +0200
Source: Sound Digest Archive v01.n386
At 19:25 12-8-98 +0200, Torbjørn Lien wrote:
>Guido,all:
>I'm much puzzeled by this,-
>
>Guido wrote:
>
>>I do, CF: have 2 inputs, the grid and the cathode (since >both
>voltages can influence the current) -have 100 % >feedback (since gain
>is about unity)
>>This looks like an operational amplifier, in follower mode, >or not ?
>Circuits like these give odd harmonics !
>
>Myselve wrote:
>
>>>Ehm,-I'm not sure what you mean here. But I guess you are
>>>reffering to a change of the spectrum of the residual >>harmonic
>distortion, so that even harmonics some how are
>>>not in proportion to the odd harmonics,-as often seen in
>>>balanced/pp amps.
>
>>Yup, that is what I mean
>
>>>I cant see how *one single* tube can accomplish this.
>>>With full voltage feedback, as in a single cathodefollover >>stage,
>the whole dist.spectrum is evenly reduced,-atleast >>in the "working
>range" of the stage.
>
>>No, it is not
>>Even this one single tube has two inputs influencing the >current. On
>one of these inputs (the cathode) full feedback >is present, the other
>is the input of the stage.
>>The problem is independant of the voltage swing
>
>[snip]
>
>Sorry, I cant find any sense in this. My point was that a
>single triodetube is something *way* different than an OP-
>amp.And the point that both circuits have 2 input terminals
>makes them in *no* way similar.So I say again: Cathodefollowers does
>not introduce exessive, or even
>altered odd harmonic distortion.
>
>There are several ways to show this.
>
>As you yourselves pointed out , this is a circuit with 100%
>neg. feedback. Now, why should a stage respond to this feed-
>back by reducing the even order harmonics more than the
>reducing of the odd order harmonics?
A differential amplifier does, for instance
>As distortion is by def.
>variation of gain through a cycle ,this gain variation is
>reduced by the feedback factor, thus the circuit *can not* differ
>between the various components of this distortion,
>reducing one type more or less than another type.
so what is the big difference between SE and PP then ?
>Another way is to look at the characteristic curves of any
>triode-tube. By noting that *all* triodes to a varying degree shares
>these basic characteristics, it is easily seen that
>a single triodetube has even harmonics as its most noticeable
>nonlinearity.
What are the conditions these curves are taken ? fixed current(s) ? fixed
voltage(s) ?
>This does *not* change by connecting the tube
>as a cathodefollower.
the final distortion depends on the circuit topology (two triodes in
perfect push-pull give odd harmonics)
>Infact, getting a single triode to
>amplify (voltage or current) with major odd order distortion is very
>difficult, the only way would be to place the working point so that
>clipping is perfectly symmetrical, and then run the stage *very* hard.
I am still talking about "normal" conditions
>To find the actual distortion in a cathodefollower, the
>easiest way, I guess is to: Take the cathodeload and connect
>to the anode, so that you get a normal common cathode stage
>with no feedback.
now you change the circuit
>Test it with some signals, so that the output voltage
>at the anode gets the same working (AC) value (as the cathodefollower
>is aimed for.) Take note of the gain,(the Rp) and of the 2. and 3.
>harmonic distortion of the stage. Now: The harmonic distortion (and
>Rp) is reduced by the gain factor when replacing the load to the
>cathode.Both 2. and 3. Theire relative magnitude is unaltered.
>
>This shows infact how valuable local feedback is as a
>construction tool, as it is only "shifting" the tubes own's
>parameters. Thus, by allowing small doses of local feedback, a slightly
>"out of spec." tube might do the trick.Or, if a
>circuit ends up with gain to spare, it might be used to something
>useful,which usually would be to linearize the
>output stage.
My basic approach is that the current trough the tube (and so its
parameters) in a CF circuit are affected by the grid-to-cathode voltage (1)
and the anode-to-cathode voltage
1 depends on grid and cathode voltage
2 depends on the cathode swing (since anode voltage is fixed)
since grid is inverting (input), and cathode non-inverting (feedback) the
whole acts as a unity gain, full feedback opamp, to my belief. the realtion
of voltages between grid and cathode is of utmost importance. The change of
current makes it worsee, that is why the current source works (keeping grid
to cathode at same value)
cascading the whole helps keeping anode to cathode constant, but this
influence (and sound impovement) is mu time smaller
Implementing both gives you a REAL follower as the cathode perfectly
follows the grid, with a constant (DC) current trough the tube (except for
the current charging the miller capacitance, but that I will solve as well;
with feedback !)
Have fun
Guido
>:TL
>>
>>
>>
>>
>
>
=========================================================================
From: "=?ISO-8859-1?Q?Torbj=F8rn_Lien?=" <mdrivekl@online.no>
Subject: Re: Cathode Followers.
Date: Thu, 13 Aug 1998 00:06:23 +0200
Source: Sound Digest Archive v01.n386
(Guido Guido,- ) :)
This thread is about single tube cathodefollowers.
(Not diff-stages.They're balancing devices, and
something completely different.. Not the SE vs.
PP, has to vait for some other time.Not sneaky
trics to further improve upon cathodefollowers
In short:
We're discussing the effects of *one single tube*,
something I find interesting, as it is claimed from
severals on this list that the cathodefollower
doesn't cut it.And *now*, that this device gives
odd order harmonics.
You wrote:[snip]
My basic approach is that the current trough the tube (and so its
parameters) in a CF circuit are affected by the grid-to-cathode voltage
(1)and the anode-to-cathode voltage
1 depends on grid and cathode voltage
2 depends on the cathode swing (since anode voltage is fixed)
??Yes, and so what?? Now, let me try a third approach to
show that the cathodefollower does not "imbalance" distortion
vs. a common cathode amplifying stage.
Picture this: A common cathode voltage amplifying triode.
The circuit is in completely series, forming a circle. This
consists of (B-pole >> cathode >> grid >> anode >> load (R+rload) >>
+pole, and then back to -pole (through zero resistance in the PSU.)This
completes the circle made up of
these three elements: Triodetube>load>Voltage source.
Now, lets examine this single stage amp. We impose an AC signal between
the cathode and grid, and notices that the signal is amplified across
the Rload, because of signal current fluctuations in the tube, or more
correct, in the
"circle". We notices some voltage gain (say 10 times, )some
distortion of the output signal across Rload (say 10% 2.harmonic, and
1% 3. harmonic.)....
Now, as this amplifier is a series circuit, it doesn't matter in what
order we hook it up. So one thing we can do immediately is to exchange
the placement of the load and the voltage source. So our amp "circle"
now look like this:
cathode >> grid >> anode >> B+pole >> B-pole >> load
>> and then back to cathode. We impose the same signal between kathode
and grid, and guess what?! We get the exact same results, distortion,-
and gain-vice across the load.
(Again: Until now we have not reffered any point to ground. Just
imposed a signal btw. cathode-grid and measured it across r-load.*NO*
difference in the two setups.)
Do you "follow" ? (Pun int :)
Now, what happens if we instead put our input signal
across *load and grid*, leaving the cathode inbetween?
First we notices that the output signal across Rload is
infact smaller than our input-signal. And, of cource,
since the two voltages are in phase, we see that cathode
"movement" is actively following the input signal, leaving
only small variations betw. cathode and grid. But we know
the cure for this: As our initial amplifier had gain of
10 times, we simply boost our test-input signal.*11* times.
So, now we get a situation related to the preveous one:
We have 1 signal "unit" between cathode and grid ,and because
of tube gain, we have 10x signal "units" across the load.
To get this, we must put in 11 signal "units."
So,-looking at this circuit, how should a *dominant* odd order
distortion occur? It cannot. As said: Harmonic distortion is per def.
variation of gain through a cycle....
In this example it meens that we infact *do not* have 10 signal units
across the load. We have 10% 2. order, and 1% 3.
order aswell,-we had initially, anyway. But as our input,
and outputsignal is referenced at the same point, things improves a
bit, as the distortion components are "modifying" the voltage betw.
grid and cathode.So, the tube receives an
ekstra signal on the cathode, the gain of the tube (10X) is amplifying
them, and because of phase leaving now only 10%:10 >> 1% 2.harmonic ,
1%:10>>0,1% 3.harmonic.
Now: Initially we had 10% 2., 1% 3. and Vgain of 10.
As a follower, we have 1% 2. , 0,1% 3. and Vg<1.
10:1 = 1:0,1=>10. The ratio 2.H to 3.H *is* unaltered.
(I'm sorry, I'm no EE,and not a teacher, try doing this
on paper.)
Guido:
since grid is inverting (input), and cathode non-inverting
(feedback)the whole acts as a unity gain, full feedback opamp, to my
belief.
[snip]
This is wrong. A triode is an extremely simple 3-electrode
amplifying device, with *finite* gain and simple transfer
functions.The simple transfer function makes it quite easy
to see what this device can, and cannot do. An OP-amp is a
rather complex, and *complete* amplifier in itselves, with a transfer
function that is utterly complex, regarding the distortion,
bandwithlimiting etc.of the various stages inside
the chip.
:TL
<sound@deliverator.io.com>
Subject: Re: Cathode Followers.
Date: 12. august 1998 19:48
At 19:25 12-8-98 +0200, Torbjørn Lien wrote:
>Guido,all:
>I'm much puzzeled by this,-
>
>Guido wrote:
>
>>I do, CF: have 2 inputs, the grid and the cathode (since >both
>voltages can influence the current) -have 100 % >feedback (since gain
>is about unity)
>>This looks like an operational amplifier, in follower mode, >or not ?
>Circuits like these give odd harmonics !
>
>Myselve wrote:
>
>>>Ehm,-I'm not sure what you mean here. But I guess you are
>>>reffering to a change of the spectrum of the residual >>harmonic
>distortion, so that even harmonics some how are
>>>not in proportion to the odd harmonics,-as often seen in
>>>balanced/pp amps.
>
>>Yup, that is what I mean
>
>>>I cant see how *one single* tube can accomplish this.
>>>With full voltage feedback, as in a single cathodefollover >>stage,
>the whole dist.spectrum is evenly reduced,-atleast >>in the "working
>range" of the stage.
>
>>No, it is not
>>Even this one single tube has two inputs influencing the >current. On
>one of these inputs (the cathode) full feedback >is present, the other
>is the input of the stage.
>>The problem is independant of the voltage swing
>
>[snip]
>
>Sorry, I cant find any sense in this. My point was that a
>single triodetube is something *way* different than an OP-
>amp.And the point that both circuits have 2 input terminals
>makes them in *no* way similar.So I say again: Cathodefollowers does
>not introduce exessive, or even
>altered odd harmonic distortion.
>
>There are several ways to show this.
>
>As you yourselves pointed out , this is a circuit with 100%
>neg. feedback. Now, why should a stage respond to this feed-
>back by reducing the even order harmonics more than the
>reducing of the odd order harmonics?
A differential amplifier does, for instance
>As distortion is by def.
>variation of gain through a cycle ,this gain variation is
>reduced by the feedback factor, thus the circuit *can not* differ
>between the various components of this distortion,
>reducing one type more or less than another type.
so what is the big difference between SE and PP then ?
>Another way is to look at the characteristic curves of any
>triode-tube. By noting that *all* triodes to a varying degree shares
>these basic characteristics, it is easily seen that
>a single triodetube has even harmonics as its most noticeable
>nonlinearity.
What are the conditions these curves are taken ? fixed current(s) ?
fixed
voltage(s) ?
>This does *not* change by connecting the tube
>as a cathodefollower.
the final distortion depends on the circuit topology (two triodes in
perfect push-pull give odd harmonics)
>Infact, getting a single triode to
>amplify (voltage or current) with major odd order distortion is very
>difficult, the only way would be to place the working point so that
>clipping is perfectly symmetrical, and then run the stage *very*
hard.
I am still talking about "normal" conditions
>To find the actual distortion in a cathodefollower, the
>easiest way, I guess is to: Take the cathodeload and connect
>to the anode, so that you get a normal common cathode stage
>with no feedback.
now you change the circuit
>Test it with some signals, so that the output voltage
>at the anode gets the same working (AC) value (as the cathodefollower
>is aimed for.) Take note of the gain,(the Rp) and of the 2. and 3.
>harmonic distortion of the stage. Now: The harmonic distortion (and
>Rp) is reduced by the gain factor when replacing the load to the
>cathode.Both 2. and 3. Theire relative magnitude is unaltered.
>
>This shows infact how valuable local feedback is as a
>construction tool, as it is only "shifting" the tubes own's
>parameters. Thus, by allowing small doses of local feedback, a
slightly
>"out of spec." tube might do the trick.Or, if a
>circuit ends up with gain to spare, it might be used to something
>useful,which usually would be to linearize the
>output stage.
My basic approach is that the current trough the tube (and so its
parameters) in a CF circuit are affected by the grid-to-cathode voltage
(1)
and the anode-to-cathode voltage
1 depends on grid and cathode voltage
2 depends on the cathode swing (since anode voltage is fixed)
since grid is inverting (input), and cathode non-inverting (feedback)
the
whole acts as a unity gain, full feedback opamp, to my belief. the
realtion
of voltages between grid and cathode is of utmost importance. The
change of
current makes it worsee, that is why the current source works (keeping
grid
to cathode at same value)
cascading the whole helps keeping anode to cathode constant, but this
influence (and sound impovement) is mu time smaller
Implementing both gives you a REAL follower as the cathode perfectly
follows the grid, with a constant (DC) current trough the tube (except
for
the current charging the miller capacitance, but that I will solve as
well;
with feedback !)
Have fun
Guido
>:TL
>>
>>
>>
>>
>
>
- ----------
=========================================================================
From: Paul Joppa <pdj@ISDNseattle.net>
Subject: Re: Cathode Followers.
Date: Wed, 12 Aug 1998 23:14:52 -0700
Source: Sound Digest Archive v01.n387
I just cut this one point out for comment:
evaguido wrote:
>
> A lower voltage swing gives absolute lower distortion, but relatively the same
>
I think that the higher order harmonics fall faster than the lower
ones as output level falls - at least that's true with a power-series
representation of nonlinearities. This may explain why some tubes make
nice RIAA preamps but lousy drivers - I'm thinking of the 6922 for
instance (which has a reputation for high 3rd harmonic based on Eric
Barbour's measurements) or the 6SL7.
- -Paul Joppa
=========================================================================
From: Grover Gardner <groverg@postoffice.att.net>
Subject: Cathode followers and other stuff
Date: Mon, 6 Jul 1998 22:07:40 -0500
Source: Sound Digest Archive v01.n334
I am starting to actually build these amps (yes!)--I ended up with parallel
12AT7 cap-coupled to parallel 5687 cap-coupled to single 5687 CF directly
coupled to VV52 grids, biased at either -75 volts or -62 volts, depending
on whether I add 100 ohms of current feedback to the output tube. I'm
still experimenting with that.
I tried a bunch of things as cathode followers. 6BL7, which was nice but
not as musical IMHO as the 5687, but it did have a big, straightforward
sound. I tried some 5992s a friend loaned me--these are snazzy-looking
mil versions of the 6V6.
I set it up in pentode mode first