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Andre Jute Andre Jute is offline
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Default KISS Amp 300B Ultrafi finalized; circuit updated

The "KISS Amp WE300B SE Ultrafi" (1) has been finalized. This is a
project that was designed step by step on rec.audio.tubes. The
amplifier is single-ended, zero negative feedback, built with Western
Electric signal and power tubes and a Mullard tube rectifier. There are
(counting by the Gaincard method which leaves the attenuator and power
supply out of the count!) six components in the signal path: 3
resistors, a cap and two tubes. It is a truly silent amplifier (It
sacrifices half the power for that silence) and in particular the
output is free of any odd harmonics. The circuit with a single WE 417A
tube doing both input and driver duty is at:
http://members.lycos.co.uk/fiultra/T...trafi-crct.jpg
The companion, somewhat simpler and less expensive "standard good" 300B
SE amplifier in the ultrafi set, the 300B SE amplifier "Populaire" with
two stages of 6SN7 tubes, has been previously published at
http://members.lycos.co.uk/fiultra/T44bis-'Populaire'-crct.jpg
Both amplfiers are described in The KISS Amp section of Jute on Amps
http://members.lycos.co.uk/fiultra/T...mp%20INDEX.htm
From the introduction: "THE KISS AMP 300B project is an attempt to take

the tube amp designer by the hand and lead him through all the highways
and byways of designing an ultrafi amp, including the thought
processes, the math and the development. It is half-engineering course,
half metaphysics, half bloodyminded prejudice and alltogether
infuriatingly complex because the simplicity of KISS has a very high
price. It has its own index page for the text and another for the
illustrations. You will find the majority of the most useful core
articles in the old Jute on Amps site in The KISS Amp 300B files,
rearranged and rewritten to make the interdependence of tube design
decisions manifest."
Suitable speakers for these amplifiers are also shown, the expensive
first
http://members.lycos.co.uk/fiultra/K...20T91HWAF3.jpg
and then the almost ridiculously cheap
http://members.lycos.co.uk/fiultra/K...Impresario.jpg
More of my amplifiers, both solid state and tube (valve) are at Jute on
Amps
http://members.lycos.co.uk/fiultra/JUTE%20ON%20AMPS.htm
You are also invited to visit my overall netsite which has information
on a couple of of my professions, as a novelist and as a typographere,
and some of my other interests: music both live and recorded which I
reviewed for many years for papers around the world, watches,
bicycling, cooking, etc.
http://members.lycos.co.uk/fiultra/

Many helped along the way by a cheery "Thanks!", or a private note
telling me not to succumb before the assaults of the silicon slime and
the other useless egomaniacs who create nothing except flamewars on the
very few remaining productive members of RAT. (For proof, read on in
the rest of this thread.)

Among those who provided relevant technical advice I must in particular
and in alphabetical order thank Steve Bench, John Byrns, Doug Bannard
and Patrick Turner. Even more admirable than their knowledge is their
patience! Controversial opinions, errors and omissions are mine, of
course.

Pay due respect to high voltage and live long!

Andre Jute
Sauvitor in modo, fortiter in res
Visit Jute on Amps at http://members.lycos.co.uk/fiultra/
"wonderfully well written and reasoned information
for the tube audio constructor"
John Broskie TubeCAD & GlassWare
"an unbelievably comprehensive web site
containing vital gems of wisdom"
Stuart Perry Hi-Fi News & Record Review

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Peter Wieck Peter Wieck is offline
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Default KISS Amp 300B Ultrafi finalized; circuit updated


Andre Jute wrote:
The "KISS Amp WE300B SE Ultrafi" (1) has been finalized.


OK... I can accept that. Now, has it been built? More importantly, does
it work?

Given the overall accuracy and credibility of the OP, I would believe
the latter two only if independently witnessed and photographed
together with a copy of a recent newspaper headline. And even then I
would be skeptical.

Peter Wieck
Wyncote, PA

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John Byrns John Byrns is offline
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Default KISS Amp 300B Ultrafi finalized; circuit updated

In article .com,
"Andre Jute" wrote:

The "KISS Amp WE300B SE Ultrafi" (1) has been finalized. This is a
project that was designed step by step on rec.audio.tubes. The
amplifier is single-ended, zero negative feedback, built with Western
Electric signal and power tubes and a Mullard tube rectifier. There are
(counting by the Gaincard method which leaves the attenuator and power
supply out of the count!) six components in the signal path: 3
resistors, a cap and two tubes.


Hi Andre,

Can you explain in more detail the "Gaincard method" of counting
components in the signal path? Ignoring the fact that you don't seem to
be including the output transformer in your count, I still can't
duplicate your count for the "KISS Amp WE300B SE Ultrafi"

In any case, six components give or take for the signal to pass through
sounds like too many for good sonics. In my "7119 PP Potato 2 Minimal"
amp the signal passes through only two components depending on exactly
how you count.

It is a truly silent amplifier (It
sacrifices half the power for that silence) and in particular the
output is free of any odd harmonics.


What is the power output of your "KISS Amp WE300B SE Ultrafi"?

The circuit with a single WE 417A
tube doing both input and driver duty is at:
http://members.lycos.co.uk/fiultra/T...trafi-crct.jpg



Regards,

John Byrns

--
Surf my web pages at, http://fmamradios.com/
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Don Pearce Don Pearce is offline
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Default KISS Amp 300B Ultrafi finalized; circuit updated

On Sun, 14 Jan 2007 13:23:13 -0600, John Byrns
wrote:

Can you explain in more detail the "Gaincard method" of counting
components in the signal path? Ignoring the fact that you don't seem to
be including the output transformer in your count, I still can't
duplicate your count for the "KISS Amp WE300B SE Ultrafi"


A much more interesting number is those components that can do
something to the signal. Those are either the ones in the direct
signal path or those that have a signal voltage across them. Some
components in the signal path have essentially zero signal voltage
across them and are thereby incapable of altering the signal.

Now, counting properly, components in the direct signal path are

Input pot
4 by 220R grid stopper
First valve
Coupling cap
220R grid stopper
Second valve
transformer
47k feedback r
200uf B1 decoupler

That's 12

The signal handling components with first order effects are

Battery
10 anode load
200uF B2 decoupler
47k grid leak
56uf cathode decoupler
1k cathode load

That makes 18 total.

Buggered if I can see the relevance of the number though. Any signal
that hits this amp has already been through a few hundred other
components. Of course the whole thing makes a bit of sense when you
consider that the components in this amp are doing a
disproportionately huge amount of damage to the signal. Which they
are. Ultrafi is an interestingly ironic name, don't you think?

d
--
Pearce Consulting
http://www.pearce.uk.com
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Don Pearce Don Pearce is offline
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Default KISS Amp 300B Ultrafi finalized; circuit updated

On Sun, 14 Jan 2007 20:07:06 GMT, (Don Pearce)
wrote:

On Sun, 14 Jan 2007 13:23:13 -0600, John Byrns
wrote:

Can you explain in more detail the "Gaincard method" of counting
components in the signal path? Ignoring the fact that you don't seem to
be including the output transformer in your count, I still can't
duplicate your count for the "KISS Amp WE300B SE Ultrafi"


A much more interesting number is those components that can do
something to the signal. Those are either the ones in the direct
signal path or those that have a signal voltage across them. Some
components in the signal path have essentially zero signal voltage
across them and are thereby incapable of altering the signal.

Now, counting properly, components in the direct signal path are

Input pot
4 by 220R grid stopper
First valve
Coupling cap
220R grid stopper
Second valve
transformer
47k feedback r
200uf B1 decoupler

That's 12

The signal handling components with first order effects are

Battery
10 anode load
200uF B2 decoupler
47k grid leak
56uf cathode decoupler
1k cathode load

That makes 18 total.

Buggered if I can see the relevance of the number though. Any signal
that hits this amp has already been through a few hundred other
components. Of course the whole thing makes a bit of sense when you
consider that the components in this amp are doing a
disproportionately huge amount of damage to the signal. Which they
are. Ultrafi is an interestingly ironic name, don't you think?

d


Sorry, miscounted. I hadn't spotted the two 100 ohm resistors and 100
ohm pot forming the series feedback network on the output valve were
carrying signal. Hang - this amp is not meant to have any feedback -
what are they doing there?

d

--
Pearce Consulting
http://www.pearce.uk.com


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Default KISS Amp 300B Ultrafi finalized; circuit updated



Don Pearce wrote:

Some components in the signal path have essentially zero signal voltage
across them and are thereby incapable of altering the signal.


Like coupling caps - LOL ! Who mentioned Teflon caps ?

Graham

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Nick Gorham Nick Gorham is offline
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Default KISS Amp 300B Ultrafi finalized; circuit updated

Andre Jute wrote:
The "KISS Amp WE300B SE Ultrafi" (1) has been finalized. This is a
project that was designed step by step on rec.audio.tubes. The


This may have been covered, in which case, sorry, but why is the signal
ground point taken back at the rectifier? Doesn't that make the output
stage signal loop include the choke and snubbers in the supply?

--
Nick
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Default KISS Amp 300B Ultrafi finalized; circuit updated



Don Pearce wrote:

On Sun, 14 Jan 2007 20:07:06 GMT, (Don Pearce)
wrote:

On Sun, 14 Jan 2007 13:23:13 -0600, John Byrns
wrote:

Can you explain in more detail the "Gaincard method" of counting
components in the signal path? Ignoring the fact that you don't seem to
be including the output transformer in your count, I still can't
duplicate your count for the "KISS Amp WE300B SE Ultrafi"


A much more interesting number is those components that can do
something to the signal. Those are either the ones in the direct
signal path or those that have a signal voltage across them. Some
components in the signal path have essentially zero signal voltage
across them and are thereby incapable of altering the signal.

Now, counting properly, components in the direct signal path are

Input pot
4 by 220R grid stopper
First valve
Coupling cap
220R grid stopper
Second valve
transformer
47k feedback r
200uf B1 decoupler

That's 12

The signal handling components with first order effects are

Battery
10 anode load
200uF B2 decoupler
47k grid leak
56uf cathode decoupler
1k cathode load

That makes 18 total.

Buggered if I can see the relevance of the number though. Any signal
that hits this amp has already been through a few hundred other
components. Of course the whole thing makes a bit of sense when you
consider that the components in this amp are doing a
disproportionately huge amount of damage to the signal. Which they
are. Ultrafi is an interestingly ironic name, don't you think?

d


Sorry, miscounted. I hadn't spotted the two 100 ohm resistors and 100
ohm pot forming the series feedback network on the output valve were
carrying signal. Hang - this amp is not meant to have any feedback -
what are they doing there?


LOL !

You nearly had me going there. That's the 'hum trim' control.

Graham

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Don Pearce Don Pearce is offline
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Default KISS Amp 300B Ultrafi finalized; circuit updated

On Sun, 14 Jan 2007 21:15:23 +0000, Eeyore
wrote:



Don Pearce wrote:

On Sun, 14 Jan 2007 20:07:06 GMT, (Don Pearce)
wrote:

On Sun, 14 Jan 2007 13:23:13 -0600, John Byrns
wrote:

Can you explain in more detail the "Gaincard method" of counting
components in the signal path? Ignoring the fact that you don't seem to
be including the output transformer in your count, I still can't
duplicate your count for the "KISS Amp WE300B SE Ultrafi"

A much more interesting number is those components that can do
something to the signal. Those are either the ones in the direct
signal path or those that have a signal voltage across them. Some
components in the signal path have essentially zero signal voltage
across them and are thereby incapable of altering the signal.

Now, counting properly, components in the direct signal path are

Input pot
4 by 220R grid stopper
First valve
Coupling cap
220R grid stopper
Second valve
transformer
47k feedback r
200uf B1 decoupler

That's 12

The signal handling components with first order effects are

Battery
10 anode load
200uF B2 decoupler
47k grid leak
56uf cathode decoupler
1k cathode load

That makes 18 total.

Buggered if I can see the relevance of the number though. Any signal
that hits this amp has already been through a few hundred other
components. Of course the whole thing makes a bit of sense when you
consider that the components in this amp are doing a
disproportionately huge amount of damage to the signal. Which they
are. Ultrafi is an interestingly ironic name, don't you think?

d


Sorry, miscounted. I hadn't spotted the two 100 ohm resistors and 100
ohm pot forming the series feedback network on the output valve were
carrying signal. Hang - this amp is not meant to have any feedback -
what are they doing there?


LOL !

You nearly had me going there. That's the 'hum trim' control.

Graham


It is also negative feedback, whether or not that is the prime
purpose.

d

--
Pearce Consulting
http://www.pearce.uk.com
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Andre Jute Andre Jute is offline
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Default KISS Amp 300B Ultrafi finalized; circuit updated


John Byrns wrote:
In article .com,
"Andre Jute" wrote:

The "KISS Amp WE300B SE Ultrafi" (1) has been finalized. This is a
project that was designed step by step on rec.audio.tubes. The
amplifier is single-ended, zero negative feedback, built with Western
Electric signal and power tubes and a Mullard tube rectifier. There are
(counting by the Gaincard method which leaves the attenuator and power
supply out of the count!) six components in the signal path: 3
resistors, a cap and two tubes.


Hi Andre,

Can you explain in more detail the "Gaincard method" of counting
components in the signal path? Ignoring the fact that you don't seem to
be including the output transformer in your count, I still can't
duplicate your count for the "KISS Amp WE300B SE Ultrafi"


Let's take Don Pearce's list, which, whatever his motives, seems
reasonable enough to me:

Input pot
4 by 220R grid stopper
First valve
Coupling cap
220R grid stopper
Second valve
transformer
47k feedback r (Pearce must be referring to the grid leak resistor)
200uf B1 decoupler

Now, the Gaincard method, which I checked into when I designed a
minimum silicon amp
http://members.lycos.co.uk/fiultra/K...dre%20Jute.htm
http://members.lycos.co.uk/fiultra/K...dre%20Jute.htm
while I waited for you and Patrick to finish educating Pinkerton so
that he could enter the design contest in which he disgraced himself,
counts only components directly in the signal line from input to
output, and ignores the attenuator and the power supply. That would
leave one with:

1 grid stopper (4x 220R grid stoppers in parallel, counted as one as
the gainclone boys do)
First valve
Coupling cap
220R grid stopper
Second valve
transformer

Hmm. That's six components by the Gaincard method; I must have
subliminally revolted against such wishful thinking and defiantly
included the attenuator as well. Still, even if I include the
attenuator, that's two less than the Gancard tally of nine. One might
argue that a grid stopper soldered to the socket itself is a continuous
part of a component which is not counted, and thus not count it. The
truth is that I don't really care how many components I use, as long as
they are the right number and quality for the sound I want; didn't
Einstein say a thing should be as simple as is necessary but no
simpler. The key thing is to know when too much has arrived and to step
back from it.

In any case, six components give or take for the signal to pass through
sounds like too many for good sonics. In my "7119 PP Potato 2 Minimal"
amp the signal passes through only two components depending on exactly
how you count.


Showoff! Reeling in shock at such parsimony, I went looking for the
circuit on your site. When will you be publishing it? It sounds
fascinating.

It is a truly silent amplifier (It
sacrifices half the power for that silence) and in particular the
output is free of any odd harmonics.


What is the power output of your "KISS Amp WE300B SE Ultrafi"?


3.8W. I know, it doesn't look like very much from a 300B, but that is
the price of silence, of loading the plate with a 5K6 primary impedance
to get the noise down and the excellent harmonic distribution which you
first pointed out back when you compared the output stage of an earlier
version of the more affordable 6SN76SN7300B version of this amp, the
T44 Populaire,
http://members.lycos.co.uk/fiultra/T44bis-'Populaire'-crct.jpg
with the amp entered against it in an earlier design competition, the
Bubbaland 300B.

The circuit with a single WE 417A
tube doing both input and driver duty is at:
http://members.lycos.co.uk/fiultra/T...trafi-crct.jpg


Regards,

John Byrns
--
Surf my web pages at, http://fmamradios.com/


Nice to see you back, John. I was thinking of discussing my next
project (a completely differential amp to drive electrostatic
earphones, what Stax calls "earspeakers on another group now that the
mouthfoamers have driven out so many of the capable RATs, but if you're
back perhaps we can inject some relevant interest. Mind you, my
dissection partner, yeah, all those years ago, had a macabre sense of
humour; he once told a female student, "Pass up that footpump so I can
inflate this cadaver and have sex with it." RAT's a bit like that these
days.

Andre Jute
Visit Jute on Amps at http://members.lycos.co.uk/fiultra/
"wonderfully well written and reasoned information
for the tube audio constructor"
John Broskie TubeCAD & GlassWare
"an unbelievably comprehensive web site
containing vital gems of wisdom"
Stuart Perry Hi-Fi News & Record Review



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Eeyore Eeyore is offline
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Default KISS Amp 300B Ultrafi finalized; circuit updated



Don Pearce wrote:

On Sun, 14 Jan 2007 21:15:23 +0000, Eeyore
wrote:



Don Pearce wrote:

On Sun, 14 Jan 2007 20:07:06 GMT, (Don Pearce)
wrote:

On Sun, 14 Jan 2007 13:23:13 -0600, John Byrns
wrote:

Can you explain in more detail the "Gaincard method" of counting
components in the signal path? Ignoring the fact that you don't seem to
be including the output transformer in your count, I still can't
duplicate your count for the "KISS Amp WE300B SE Ultrafi"

A much more interesting number is those components that can do
something to the signal. Those are either the ones in the direct
signal path or those that have a signal voltage across them. Some
components in the signal path have essentially zero signal voltage
across them and are thereby incapable of altering the signal.

Now, counting properly, components in the direct signal path are

Input pot
4 by 220R grid stopper
First valve
Coupling cap
220R grid stopper
Second valve
transformer
47k feedback r
200uf B1 decoupler

That's 12

The signal handling components with first order effects are

Battery
10 anode load
200uF B2 decoupler
47k grid leak
56uf cathode decoupler
1k cathode load

That makes 18 total.

Buggered if I can see the relevance of the number though. Any signal
that hits this amp has already been through a few hundred other
components. Of course the whole thing makes a bit of sense when you
consider that the components in this amp are doing a
disproportionately huge amount of damage to the signal. Which they
are. Ultrafi is an interestingly ironic name, don't you think?

d

Sorry, miscounted. I hadn't spotted the two 100 ohm resistors and 100
ohm pot forming the series feedback network on the output valve were
carrying signal. Hang - this amp is not meant to have any feedback -
what are they doing there?


LOL !

You nearly had me going there. That's the 'hum trim' control.

Graham


It is also negative feedback, whether or not that is the prime
purpose.


It will introduce a smidgen of NFB for sure.

Graham

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Default KISS Amp 300B Ultrafi finalized; circuit updated

Don Pearce wrote:
On Sun, 14 Jan 2007 20:07:06 GMT, (Don Pearce)
wrote:

On Sun, 14 Jan 2007 13:23:13 -0600, John Byrns
wrote:

Can you explain in more detail the "Gaincard method" of counting
components in the signal path? Ignoring the fact that you don't seem to
be including the output transformer in your count, I still can't
duplicate your count for the "KISS Amp WE300B SE Ultrafi"


A much more interesting number is those components that can do
something to the signal. Those are either the ones in the direct
signal path or those that have a signal voltage across them. Some
components in the signal path have essentially zero signal voltage
across them and are thereby incapable of altering the signal.

Now, counting properly, components in the direct signal path are

Input pot
4 by 220R grid stopper
First valve
Coupling cap
220R grid stopper
Second valve
transformer
47k feedback r
200uf B1 decoupler

That's 12


Thanks for the effort, Pearce. I wasn't seriously putting forward the
Gaincard method of counting, just throwing it in for discussion while I
get on with the business of designing and building my next amp.

However, the grid leak resistor which you call the "47k feedback r"
raises an interesting point of difference between the silicon crowd and
the zero negative feedback ultrafidelista faithful. You intend to mean
by negative feedback *any* feedback. By convention tubies in general
and ultrafidelista in particular by negative feedback mean global or
universal or loop negative feedback, certainly nothing contained within
one stage of any of the classical topologies (including those newly
revived like the mu stage). Even a cathode follower, surely a feedback
device!, is kosher to the ZNFB crowd, and they have often resented me
for pointing it out as much as the silicon slime has resented me for
pointing out *their* wishful thinking and other depredations on the
immutable laws of physics. (Hey, there are some tubies who still want
to lynch me ten years later for puncturing their bubble on SRPP, which
until I made an irrefutable analysis they happily promoted for thirty
years as a constant current-loaded triode, which of course it isn't.)

The signal handling components with first order effects are

Battery
10 anode load
200uF B2 decoupler
47k grid leak
56uf cathode decoupler
1k cathode load

That makes 18 total.


You counted the "47k feedback r" (the grid leak, without which the amp
won't work) twice.

Buggered if I can see the relevance of the number though. Any signal
that hits this amp has already been through a few hundred other
components. Of course the whole thing makes a bit of sense when you
consider that the components in this amp are doing a
disproportionately huge amount of damage to the signal. Which they
are. Ultrafi is an interestingly ironic name, don't you think?


It is rather interesting that you don't ask for the noise figures of my
tube amp before you start spouting condemnations based on your
prejudicial preference for silicon bodged nearly right with excessive
negative feedback.

Perhaps you should at least draw the loadline on the tube transfer
curves and calculate the distortion before you spout off, Pearce. If
you know how, of course. You might surprise yourself. (I hesitate to
suggest that you build the design and measure for yourself; I wouldn't
want you to electrocute yourself on unaccustomed high voltage or burn
yourself with your new soldering iron.)

d


Sorry, miscounted. I hadn't spotted the two 100 ohm resistors and 100
ohm pot forming the series feedback network on the output valve were
carrying signal. Hang - this amp is not meant to have any feedback -
what are they doing there?


They're humbusters for the AC filaments. You do know that DC filaments
on DHT sound like ****, don't you, Pearce? Now go on, tell me about the
joys of regulation.

d

--
Pearce Consulting
http://www.pearce.uk.com

Always great to hear from you, Pearce. It gives me a warm glow of
superiority that a famous engineer like you, a proven hostile to tube
amps, can find only twee tiny quibbles when I publish a design.

Andre Jute
Visit Jute on Amps at http://members.lycos.co.uk/fiultra/
"wonderfully well written and reasoned information
for the tube audio constructor"
John Broskie TubeCAD & GlassWare
"an unbelievably comprehensive web site
containing vital gems of wisdom"
Stuart Perry Hi-Fi News & Record Review

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Default KISS Amp 300B Ultrafi finalized; circuit updated


Nick Gorham wrote:
Andre Jute wrote:
The "KISS Amp WE300B SE Ultrafi" (1) has been finalized. This is a
project that was designed step by step on rec.audio.tubes. The


This may have been covered, in which case, sorry, but why is the signal
ground point taken back at the rectifier? Doesn't that make the output
stage signal loop include the choke and snubbers in the supply?

--
Nick


Aha! At last, a substantive point. Where in my amp would you take off
the ground for the power supply, Nick? Same question to everyone who's
ever built a tube amp; don't just assume Nick will give the same answer
you will. Grounding is one of the last, possibly the last, unexplored
frontiers in hi-fidelity tube amplifiers.

I'll explain what I actually do, what I consider optimum when possible,
and what others have done when we have your answer and reasoning to
hand.

Andre Jute
Visit Jute on Amps at http://members.lycos.co.uk/fiultra/
"wonderfully well written and reasoned information
for the tube audio constructor"
John Broskie TubeCAD & GlassWare
"an unbelievably comprehensive web site
containing vital gems of wisdom"
Stuart Perry Hi-Fi News & Record Review

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Default KISS Amp 300B Ultrafi finalized; circuit updated



Andre Jute wrote:

You do know that DC filaments on DHT sound like ****, don't you


Do tell more !

Graham

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Default KISS Amp 300B Ultrafi finalized; circuit updated

Andre Jute wrote:

Nick Gorham wrote:

Andre Jute wrote:

The "KISS Amp WE300B SE Ultrafi" (1) has been finalized. This is a
project that was designed step by step on rec.audio.tubes. The


This may have been covered, in which case, sorry, but why is the signal
ground point taken back at the rectifier? Doesn't that make the output
stage signal loop include the choke and snubbers in the supply?

--
Nick



Aha! At last, a substantive point. Where in my amp would you take off
the ground for the power supply, Nick? Same question to everyone who's
ever built a tube amp; don't just assume Nick will give the same answer
you will. Grounding is one of the last, possibly the last, unexplored
frontiers in hi-fidelity tube amplifiers.

I'll explain what I actually do, what I consider optimum when possible,
and what others have done when we have your answer and reasoning to
hand.


Well, its a loaded question, as without building and testing, I am not
certain that I would use the common mode choke. Or if I did and found it
offered improved noise performance I would use a WE or ultrapath bipass
arangement to avoid the problem. Without that, I would see what the
issue was with grounding after the choke, with the expectation that it
would possibly introduce switching noise from the mains TX, which may
well defeat the use of the CM choke in the first place.

Personally I would use a series regulator in the supply (either
referenced to a voltage ref, or just as a shunt) and not the CM choke,
as I have found that they sound better than anything else I have tried.

So, what was your findings?

--
Nick


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Default KISS Amp 300B Ultrafi finalized; circuit updated

Nick Gorham wrote:

So, what was your findings?


Nick:

You need to understand that Mr. McCoy's fantasy amplifier not much more
than a mare's nest of wires and cobbled parts obtained as "samples" for
other purposes than their proposed present use. That explains
peculiarities in the power-supply, the lack of a mains-generated bias
supply, dropping resistors on the filament supplies and so forth. Also,
as it happens, the presence of feedback despite the no-feedback claim.
You may also be dead-sure that it has never seen a signal applied that
actually resulted in something happening at a speaker... at least that
was planned anyway.

After all, transformers with "correct" filament supplies are readily
available. Even from Lundhal. That should be your first clue. And if an
amp is based on rather expensive boutique tubes, it would just about
make sense that the rest of the parade would be chosen with similar
care.

You are micturating in a windward direction if you expect to get any
sort of cogent answers based on actual results from this particular
concatenation of anecdotes.

Peter Wieck
Wyncote, PA

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Default KISS Amp 300B Ultrafi finalized; circuit updated


flipper wrote:
Andre Jute wrote:

You do know that DC filaments on DHT sound like ****, don't you


I, too, would like to hear that explained.


You build tube amps to have the tone quality under your own control.
Most audiophiles arrived there by observing that silicon amps do not
faithfully reproduce the experience of the concert hall.

Then why build tube amps (expensive, inefficient, expensive, hot,
expensive, dangerous, expensive) to sound just like silicon amps? What
you do with the filaments has much to do with the sound you get.

The big modern innovation in silicon amps is actually the constant
current source, not the silicon itself, which is fundamentally
inferior, requiring very much NFB to linearize it. The effect of all
those CCS is to nail down every voltage and every current that in tube
amps in classical times were much freer (they weren't totally free and
the constant current source was not unknown in tube amps either, for
instance in certain WE topologies).

The key thing about the sort of big American tube amp that sounds to me
and many others just like silicon and therefore a big waste of money is
that it ties down all the voltages with regulation: plate, bias,
filaments, everything is very well regulated.

Now return this whole thing from the region of argument to the region
of taste. Audio is not a technical argument but an exercise in
psychoacoustics; that's why the speakers are so much more important
than the amp. Take a banksa6550 amp and first of all change the
invariably series regulation for shunt regulation, everywhere. This
will cost much more (it drops as much current in regulation as the
tubes consume, usually more than that). Already the amp sounds better.
Now remove the regulation in any order you please. Step by step the amp
sounds more natural. Now, DC is a form of regulating the current; all
rectification is. If the other forms of regulation decreased the
ambience of the amp, its closeness to a window on the concert hall,
then so will the removal of the crudest form of regulation, DC. I
haven't touched yet on another form of regulation, which is
overcapping. You might get none of the aural benefits of removing
series regulation, etc, until you remove capacitance to leave only the
correct amount for the operatng points of your tubes.

This sort of engineering development to find the place where some
obsessed meterhead went too far never fails to stun me with the fine
amps that hide inside the most unpromising examples. (Okay, this
assumes that you start with the most expensive and reputable, the only
people with the money for over-engineering, but we are far, far beyond
rational considerations of cost in this thread.)

By the way, the scale of the amp might have something to do with
whether and which currents you want to tie down to an anvil. We shall
see examples in my next project, which is a tube amp for electrostatic
headspeakers.

As I say, Flipper, prove it for yourself by going too far and
discovering that your sound has dried out like an old maid. I'm not
trying to persuade you of anything, just telling you what I did and how
I arrived at the decision.

Andre Jute
Visit Jute on Amps at http://members.lycos.co.uk/fiultra/
"wonderfully well written and reasoned information
for the tube audio constructor"
John Broskie TubeCAD & GlassWare
"an unbelievably comprehensive web site
containing vital gems of wisdom"
Stuart Perry Hi-Fi News & Record Review

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Default KISS Amp 300B Ultrafi finalized; circuit updated



Andre Jute wrote:

flipper wrote:
Andre Jute wrote:

You do know that DC filaments on DHT sound like ****, don't you

I, too, would like to hear that explained.


You build tube amps to have the tone quality under your own control.
Most audiophiles arrived there by observing that silicon amps do not
faithfully reproduce the experience of the concert hall.


Absence of any answer noted.

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Just one question - why the battery?


OK 2 questions... why the 4 paralleled input resistors? Noise?

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On 14 Jan 2007 16:01:40 -0800, "Andre Jute" wrote:

Grounding is one of the last, possibly the last, unexplored
frontiers in hi-fidelity tube amplifiers.


Hopefully not the last, but certainly one of the most
important, and definitely *the most* ignored for
typical homebrew (and, sadly, too many commercial)
designs.

Much thanks, as always,

Chris Hornbeck
"History consists of truths which in the end turn into lies,
while myth consists of lies which finally turn into truths."
- Jean Cocteau


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Default KISS Amp 300B Ultrafi finalized; circuit updated



Chris Hornbeck wrote:

On 14 Jan 2007 16:01:40 -0800, "Andre Jute" wrote:

Grounding is one of the last, possibly the last, unexplored
frontiers in hi-fidelity tube amplifiers.


Hopefully not the last, but certainly one of the most
important, and definitely *the most* ignored for
typical homebrew (and, sadly, too many commercial)
designs.


In pro-audio it's been well to the fore since the very beginning of the sector.
There are no secrets about good grounding practice.

Graham

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Default KISS Amp 300B Ultrafi finalized; circuit updated

In article ,
Eeyore wrote:

Andre Jute wrote:

flipper wrote:
Andre Jute wrote:

You do know that DC filaments on DHT sound like ****, don't you

I, too, would like to hear that explained.


You build tube amps to have the tone quality under your own control.
Most audiophiles arrived there by observing that silicon amps do not
faithfully reproduce the experience of the concert hall.


Absence of any answer noted.


It sounded like an answer to me, essentially what he suggested was that
you try it both with DC, and then with AC and choose the one that sounds
best to you. A lot of people seem to prefer the sonics of AC heating,
and I will give it my vote too, the only major downside of AC heating
being a greater difficulty in banishing the last vestiges of hum. I
suspect you are actually looking for an explanation of the physics that
make AC heating sound better than DC heating, but the important thing is
the sound.


Regards,

John Byrns

--
Surf my web pages at, http://fmamradios.com/
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Default KISS Amp 300B Ultrafi finalized; circuit updated

On Mon, 15 Jan 2007 03:57:58 +0000, Eeyore
wrote:

Hopefully not the last, but certainly one of the most
important, and definitely *the most* ignored for
typical homebrew (and, sadly, too many commercial)
designs.


In pro-audio it's been well to the fore since the very beginning of the sector.
There are no secrets about good grounding practice.


Production sound uses balanced interconnections between
multiple pieces of equipment. Internally, the same issues
arise in the same ways, because the signal path is
unbalanced internally.

And, of course, power supplies are "unbalanced" from a
signal point of view.

This is definitely *not* a done deal; it's, instead, an
important and mostly overlooked component of the signal
path.

There are no secrets about good grounding practice, but
there are also no magic bullets. All grounding practices
are compromises among various competing goals.

Chris Hornbeck
"History consists of truths which in the end turn into lies,
while myth consists of lies which finally turn into truths."
- Jean Cocteau
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Default KISS Amp 300B Ultrafi finalized; circuit updated

On Mon, 15 Jan 2007 02:09:02 +0000, Eeyore
wrote:

You do know that DC filaments on DHT sound like ****, don't you

I, too, would like to hear that explained.

Absence of any answer noted.


The answer is easily derived from basic principles, or
even from a Google search on this newsgroup. It ain't
rocket surgery.

Chris Hornbeck
"History consists of truths which in the end turn into lies,
while myth consists of lies which finally turn into truths."
- Jean Cocteau
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On 13 Jan 2007 21:53:17 -0800, "Andre Jute" wrote:

http://members.lycos.co.uk/fiultra/T...trafi-crct.jpg


There's a typo in the posted schematic; earth ground
in the B+ supply is shown on the wrong side of the
filtering (dual-winding) choke. Otherwise, copacetic!

All good fortune,

Chris Hornbeck
"History consists of truths which in the end turn into lies,
while myth consists of lies which finally turn into truths."
- Jean Cocteau


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Default KISS Amp 300B Ultrafi finalized; circuit updated

Nick Gorham wrote:
Andre Jute wrote:

Nick Gorham wrote:

Andre Jute wrote:

The "KISS Amp WE300B SE Ultrafi" (1) has been finalized. This is a
project that was designed step by step on rec.audio.tubes. The

This may have been covered, in which case, sorry, but why is the signal
ground point taken back at the rectifier? Doesn't that make the output
stage signal loop include the choke and snubbers in the supply?

--
Nick



Aha! At last, a substantive point. Where in my amp would you take off
the ground for the power supply, Nick? Same question to everyone who's
ever built a tube amp; don't just assume Nick will give the same answer
you will. Grounding is one of the last, possibly the last, unexplored
frontiers in hi-fidelity tube amplifiers.

I'll explain what I actually do, what I consider optimum when possible,
and what others have done when we have your answer and reasoning to
hand.


Well, its a loaded question, as without building and testing, I am not
certain that I would use the common mode choke. Or if I did and found it
offered improved noise performance I would use a WE or ultrapath bipass
arangement to avoid the problem. Without that, I would see what the
issue was with grounding after the choke, with the expectation that it
would possibly introduce switching noise from the mains TX, which may
well defeat the use of the CM choke in the first place.

Personally I would use a series regulator in the supply (either
referenced to a voltage ref, or just as a shunt) and not the CM choke,
as I have found that they sound better than anything else I have tried.

So, what was your findings?

--
Nick


Nick

I wrote you a long letter which fortunately was not delivered and then
actually looked at the circuit. What happened is that I added the
snubbers over the chokes at the last moment, before sending the circuit
to the net. Before that the power filter had a star ground, the input
had a star ground, both were the same star ground, so it didn't really
matter where I parked the earth while I did major surgery on the
schematic to make space for the snubbers (1), and then I just
overlooked moving it again. It is exactly for this kind of correction
that I post the schematic to RAT and UKRA before making any other
public announcement. (It's a pity that some resident quarterwits take
that as a license to indulge in childishness, but strictly for such
self-selecting fools I do a little sleight of hand with (Gain) cards
and simple stuff about bike computers they can look up, then they go
off on a wild rabbit chase and fall over their own feet at the same
time, as intended, much to the amusement of the rest of us.)

In more "normal" or simple supplies I routinely use the earthy end of
the bleeder at the end of the supply as a star ground. You can see a
one here,
http://members.lycos.co.uk/fiultra/K...0T68MZ417A.jpg
where the bleeder is the ali-cased resistor behind the right-hand
battery box and its right end is the star earth for all sections.

Thanks for your help. I'd like you to contribute when we discuss my
next project.

Andre Jute
Visit Jute on Amps at http://members.lycos.co.uk/fiultra/
"wonderfully well written and reasoned information
for the tube audio constructor"
John Broskie TubeCAD & GlassWare
"an unbelievably comprehensive web site
containing vital gems of wisdom"
Stuart Perry Hi-Fi News & Record Review

(1) The choke snubbers seem to have little sonic benefit. They protect
the longevity of the chokes and the power tranny, all of them expensive
items.

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Default KISS Amp 300B Ultrafi finalized; circuit updated

Chris Hornbeck wrote:

On 13 Jan 2007 21:53:17 -0800, "Andre Jute" wrote:

http://members.lycos.co.uk/fiultra/T...trafi-crct.jpg


There's a typo in the posted schematic; earth ground
in the B+ supply is shown on the wrong side of the
filtering (dual-winding) choke. Otherwise, copacetic!


Thanks, Chris. That problem crept in when I put in the snubbers on the
chokes. Before, that whole circuit was starred and its star coincided
with the signal circuit star, so it didn't matter where I put the
symbol, as I explained to Nick (in a post that hours later I still
can't see).

I've now moved the earth to the other side of the chokes and all the
snubbers and posted an amended circuit to avoid misunderstandings. It
is for precisely this sort of information that I publish the circuit
first to RAT, so that the knowledgeable sharpeyed can point details
that through overfamiliarity I missed.

All good fortune,

Chris Hornbeck
"History consists of truths which in the end turn into lies,
while myth consists of lies which finally turn into truths."
- Jean Cocteau


Thanks again! (No footnotes; you can stop here.)

Andre Jute
Visit Jute on Amps at http://members.lycos.co.uk/fiultra/
"wonderfully well written and reasoned information
for the tube audio constructor"
John Broskie TubeCAD & GlassWare
"an unbelievably comprehensive web site
containing vital gems of wisdom"
Stuart Perry Hi-Fi News & Record Review

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wrote:
Just one question - why the battery?


This is the circuit under discussion:
http://members.lycos.co.uk/fiultra/T...trafi-crct.jpg

All components have sonic signature. Some have very little, or are
difficult to use for sound shaping.

There is absolutely no point in building an amp this expensive unless
for some purpose beyond the bragging rights of "I have Western Electric
300Bs in my amp, which of course I built myself." A good purpose is to
take charge of the quality of your sound, rather than leave it in the
hands of some zero-culture, long-since deaf, totally uncivilized,
supercilious, smug silicon slime, of which we can see ample samples on
these conferences. (There are also some very cultured and agreeable
silicon designers but they are successful and don't need my help.)

The WE417A driver tube was chosen for its particular signature. I had
already designed a much more precise reference SE300B amp for Western
Electric tubes with two 6SN7 stages, of which the most popular version
is he
http://members.lycos.co.uk/fiultra/T44bis-'Populaire'-crct.jpg
But in the T39 I was stepping back, building an amp for hedonists, not
soulless technicians. The 417A is very suitable for hedonists, very
linear (but not as linear as a 6SN7), quite a bit warmer in the manner
of the double digit veteran directly heated triodes but much more
widely available. Count what besides the 417A is in that circuit. The
attenuator is a DACT, built by robots on Swiss goldplated switches with
SMD resistors: zero signature, as it should be. I have no belief in
anything more than marginal soundshaping with resistors; Kiwame are
slightly but perceptibly warmer than the common Beyschlagg I also like,
and the rest leave me indifferent to the difference between them, if
any; I believe in overspeccing my resistors to run them cool and so
avoid various kinds of resistor noise which can be important in small
signal circuits.

So that leaves the tube itself, whose sound we can shape by the value
of the resistor in the plate circuit and whatever we decide to put in
the cathode circuit. Taking the plate circuit first, we can lower the
resistor value and thereby make the sound dirtier at the volume
extremes, which to the uninitiated might sound like more bass
(analogous to what you hear on boomboxes on the street or from little
passing hatchbacks owned by wannabe gangsta but of course not degraded
quite that far). That isn't quite my style, so I load the plate up to
the maximum I can within the available power supply, thereby
linearizing the response. I should explain that my style is first to
extract the maximum silence that good engineering allows, which from
tubes is much more impressive than you might imagine when you read the
silicon slime who hang out here to tell us how wrong we are because
they can't get any other employment. After that I back off to a
suitable level of hedonism. This isn't quite euphonious distortion, it
is more like a sense of balance and perspective, and an understanding
of psychoacoustics (I'm by training an economist and psychologist).

At this point we can then choose from four ways to implement a cathode
circuit. One, by constant current sink, I dismiss immediately as too
complicated for an amp announced as KISS (keep it simple, stupid); in
my next project I shall return to CCS because there their complication
is the least of the evils. That leaves three ways of doing it: a
resistor alone, a resistor bypassed by a cap, and battery bias.

Of these, the bypassed resistor is my instinctive fave. It is simple,
it is selfadjusting, and if you spend the time and the money on
development and components, you will eventually choose the right
capacitor; I have long since done my homework and know what I will use.
Open another circuit:
http://members.lycos.co.uk/fiultra/t...17acircuit.jpg
This is a complete amp built only from the first stage of the T39 (in
fact it was made by removing the 300B from a T39). It should now become
clear to you that if I substitute the battery with a resistor and a
cap), the cap becomes the sole determinant of the sonic quality of the
stage. With so little in the circuit, the cap really looms large. An
unbypassed resistor has feedback which changes the sound adversely by
making it harder, more crystalline and by tilting the response towards
the bass when in fact I want to tilt the 417A's "natural" tendency the
other way -- I just want a slightly warm amp, not a hot, gushy amp.
That leaves a battery, which, while not a soundshaping element under my
control (in that there is only one choice of operating conditions for a
417A with battery bias if you already decided the plate voltage), is at
least perfectly neutral. The battery also has a tendency to stabilize
everything around it which is a good thing as I have already paid a
heavy price in efficiency for ballasts and other devices to stablilize
important electrical points and any"free" margin is welcome.

So, by a process of elimination, I am left only with the battery. This
thought process is described in
http://members.lycos.co.uk/fiultra/T...mp%20INDEX.htm

If you study the T68bis "Minus Zero" circuit even cursorily, you will
immediately see that the other big sonic influence, besides a putative,
potential, possible cathode bypass cap, is the power supply. But that
is fully developed and fixed in a desirable sonic already, and is
anyway a large loose cannon on deck if you lose control of it, so you
don't want to mess with success if instead you can do the job by
working with one or at most two cathode circuit components, which
brings us back to the battery decision, which by its impedance in turn
makes any remaining solecism of the power supply a moot point.

All roads lead to Rome. In the T68bis you can see how all currents must
pass through that battery. It is the very dream of every control freak,
though the wannabe control freaks on RAT and UKRA lack the subtlety to
understand what is happening.

OK 2 questions... why the 4 paralleled input resistors? Noise?


The WE417A has wonderful sonics once the designer grasps how to handle
it; in the hands of the usual pretenders it quickly turns to expensive
noise because nobody told them it is a radio frequency tube. Almost all
tubes are, of course, but the 417A is especially efficient in the RF.
It has four grid pins which can pick up radio rubbish, so each one
requires a grid stopper and the signal can be put in to any of them,
though one is better than the others by far for simple reasons of
physics that may be determined by observation.

HTH.

If this is more information than you wanted, next time don't ask such
a(n only apparently) simple question!

Andre Jute
Visit Jute on Amps at http://members.lycos.co.uk/fiultra/
"wonderfully well written and reasoned information
for the tube audio constructor"
John Broskie TubeCAD & GlassWare
"an unbelievably comprehensive web site
containing vital gems of wisdom"
Stuart Perry Hi-Fi News & Record Review

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John Byrns wrote:
In article ,
Eeyore wrote:

Andre Jute wrote:

flipper wrote:
Andre Jute wrote:

You do know that DC filaments on DHT sound like ****, don't you

I, too, would like to hear that explained.

You build tube amps to have the tone quality under your own control.
Most audiophiles arrived there by observing that silicon amps do not
faithfully reproduce the experience of the concert hall.


Absence of any answer noted.


It sounded like an answer to me, essentially what he suggested was that
you try it both with DC, and then with AC and choose the one that sounds
best to you. A lot of people seem to prefer the sonics of AC heating,
and I will give it my vote too, the only major downside of AC heating
being a greater difficulty in banishing the last vestiges of hum. I
suspect you are actually looking for an explanation of the physics that
make AC heating sound better than DC heating, but the important thing is
the sound.


I can't see why Poopie should need the physics explained to him. He
claims to be an engineering graduate of the University of London.
Surely, he should be explaining the physics to us, rather than the
other way round.

And Poopie should be explaining to us those entirely unconspiratorial
grounding schemes which he smugly bragged of to Chris.

It is past high time Poopie started pulling his weight and contributing
something beyond snide soundbites if he wants to be accepted here.

I'm working, you're working, Chris is working, Nick is working, so why
isn't Poopie working?

Regards,

John Byrns
--
Surf my web pages at, http://fmamradios.com/


And one has to wonder if Poopie is blind to have missed the following
extended explanation of the points on which I make my decision between
AC and DC filaments, or if Poopie's soundbite mode of speech extends
also to his comprehension of plain English.

flipper wrote:
Andre Jute wrote:


You do know that DC filaments on DHT sound like ****, don't you


I, too, would like to hear that explained.


You build tube amps to have the tone quality under your own control.
Most audiophiles arrived there by observing that silicon amps do not
faithfully reproduce the experience of the concert hall.

Then why build tube amps (expensive, inefficient, expensive, hot,
expensive, dangerous, expensive) to sound just like silicon amps? What
you do with the filaments has much to do with the sound you get.

The big modern innovation in silicon amps is actually the constant
current source, not the silicon itself, which is fundamentally
inferior, requiring very much NFB to linearize it. The effect of all
those CCS is to nail down every voltage and every current that in tube
amps in classical times were much freer (they weren't totally free and
the constant current source was not unknown in tube amps either, for
instance in certain WE topologies).

The key thing about the sort of big American tube amp that sounds to me

and many others just like silicon and therefore a big waste of money is

that it ties down all the voltages with regulation: plate, bias,
filaments, everything is very well regulated.

Now return this whole thing from the region of argument to the region
of taste. Audio is not a technical argument but an exercise in
psychoacoustics; that's why the speakers are so much more important
than the amp. Take a banksa6550 amp and first of all change the
invariably series regulation for shunt regulation, everywhere. This
will cost much more (it drops as much current in regulation as the
tubes consume, usually more than that). Already the amp sounds better.
Now remove the regulation in any order you please. Step by step the amp

sounds more natural. Now, DC is a form of regulating the current; all
rectification is. If the other forms of regulation decreased the
ambience of the amp, its closeness to a window on the concert hall,
then so will the removal of the crudest form of regulation, DC. I
haven't touched yet on another form of regulation, which is
overcapping. You might get none of the aural benefits of removing
series regulation, etc, until you remove capacitance to leave only the
correct amount for the operatng points of your tubes.

This sort of engineering development to find the place where some
obsessed meterhead went too far never fails to stun me with the fine
amps that hide inside the most unpromising examples. (Okay, this
assumes that you start with the most expensive and reputable, the only
people with the money for over-engineering, but we are far, far beyond
rational considerations of cost in this thread.)

By the way, the scale of the amp might have something to do with
whether and which currents you want to tie down to an anvil. We shall
see examples in my next project, which is a tube amp for electrostatic
headspeakers.

As I say, Flipper, prove it for yourself by going too far and
discovering that your sound has dried out like an old maid. I'm not
trying to persuade you of anything, just telling you what I did and how

I arrived at the decision.

Andre Jute
Visit Jute on Amps at http://members.lycos.co.uk/fiultra/
"wonderfully well written and reasoned information
for the tube audio constructor"
John Broskie TubeCAD & GlassWare
"an unbelievably comprehensive web site
containing vital gems of wisdom"
Stuart Perry Hi-Fi News & Record Review



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Default KISS Amp 300B Ultrafi finalized; circuit updated



John Byrns wrote:

Eeyore wrote:
Andre Jute wrote:

flipper wrote:
Andre Jute wrote:

You do know that DC filaments on DHT sound like ****, don't you

I, too, would like to hear that explained.

You build tube amps to have the tone quality under your own control.
Most audiophiles arrived there by observing that silicon amps do not
faithfully reproduce the experience of the concert hall.


Absence of any answer noted.


It sounded like an answer to me, essentially what he suggested was that
you try it both with DC, and then with AC and choose the one that sounds
best to you.


Yes that's how I'd do it too !


A lot of people seem to prefer the sonics of AC heating,
and I will give it my vote too, the only major downside of AC heating
being a greater difficulty in banishing the last vestiges of hum. I
suspect you are actually looking for an explanation of the physics that
make AC heating sound better than DC heating, but the important thing is
the sound.


The important thing to me that there is a real difference. I can speculate about
the physics involved, I've taken a stab at it before. I was wondering perhaps if
Jootikins had come across any explanation in his travels.

My suspicion is that if there's an audible difference it may be amplitude
modulation of the signal at 2 x line frequency. That hardly bodes well for the
'purity' or 'fidelity' of such an amplifier ! It may be an interesting effect
for sure though.

Graham

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Chris Hornbeck wrote:

Eeyore wrote:

Hopefully not the last, but certainly one of the most
important, and definitely *the most* ignored for
typical homebrew (and, sadly, too many commercial)
designs.


In pro-audio it's been well to the fore since the very beginning of the sector.
There are no secrets about good grounding practice.


Production sound uses balanced interconnections between
multiple pieces of equipment.


That certainly helps a lot but I've run 60 metre ( 200 feet ) cable runs unbalanced
and still had excellent results.


Internally, the same issues arise in the same ways, because the signal path is
unbalanced internally.


Indeed so for the most part but I do also run critical signals internally balanced
too ( particularly when that signal is being transferred from one pcb to another for
example ).


And, of course, power supplies are "unbalanced" from a
signal point of view.


Ummmm.... are they ?


This is definitely *not* a done deal; it's, instead, an
important and mostly overlooked component of the signal
path.

There are no secrets about good grounding practice, but
there are also no magic bullets. All grounding practices
are compromises among various competing goals.


The are some excellent principles that get you out of most trouble. Taking it to the
limit is where it sorts the men from the boys.

Graham

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Chris Hornbeck wrote:

Eeyore wrote:

You do know that DC filaments on DHT sound like ****, don't you

I, too, would like to hear that explained.

Absence of any answer noted.


The answer is easily derived from basic principles, or
even from a Google search on this newsgroup. It ain't
rocket surgery.


I just posted my thoughts on the matter.

How about yours ?

Graham

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Andre Jute wrote:

John Byrns wrote:

I suspect you are actually looking for an explanation of the physics that
make AC heating sound better than DC heating, but the important thing is
the sound.


I can't see why Poopie should need the physics explained to him. He
claims to be an engineering graduate of the University of London.
Surely, he should be explaining the physics to us, rather than the
other way round.


It was discussed in some reasonable depth here quite recently in fact.


And one has to wonder if Poopie is blind to have missed the following
extended explanation of the points on which I make my decision between
AC and DC filaments


Your 'extended explanation' was no more than plain waffle.

Graham



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Default Why you should feel sorry for Brian McCarty, the loser who tries to persecute Bob Morein


Brian McCarty, pretending to be Robert Morein, wrote:
In article , "Andre Jute"
wrote:

I've now moved the earth to the other side of the chokes and all the
snubbers and posted an amended circuit to avoid misunderstandings. It
is for precisely this sort of information that I publish the circuit
first to RAT, so that the knowledgeable sharpeyed can point details
that through overfamiliarity I missed.


Apology accepted, with the proviso that you change "overfamiliarity" (sic)
to the more accurate "profound stupidity".

Bob Morein
Dresher, PA
(215) 646-4894


Yo, McCarty, I feel sorry for you. If Bob Morein is really such an
inferior person as you claim, how come he bust a con on which you
worked years? If Bob Morein is really as incompetent as you claim, how
come only the minority of psychopathic lepers in even the hostile
environment of the Usenet believes you?

I feel sorry for you, McCarty. I really do. You're a loser, you were
born a loser, you'll die hungry.

BTW, if you were smart, instead of crossing Robert Morein, you would
have recruited him. He's a holy fool and anyone who can harness the
force of such can be rich. I know, I worked in advertising. You're too
thick and slow for your own good, McCarty. You'll be no loss to the
gene pool.

Andre Jute

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Default KISS Amp 300B Ultrafi finalized; circuit updated


Eeyore wrote:
Chris Hornbeck wrote:

Eeyore wrote:

You do know that DC filaments on DHT sound like ****, don't you

I, too, would like to hear that explained.
Absence of any answer noted.


The answer is easily derived from basic principles, or
even from a Google search on this newsgroup. It ain't
rocket surgery.


I just posted my thoughts on the matter.


No, Poopie, you didn't post any "thoughts" on the matter.

What happenened was that John Byrns kindly explained *my* thoughts on
the matter to you in a soundbite format suitable to your intelliigence
and that you then agreed with me.

Jute:
You build tube amps to have the tone quality under your own control.
Most audiophiles arrived there by observing that silicon amps do not
faithfully reproduce the experience of the concert hall.


Poopie tries to be smart:
Absence of any answer noted.


Byrns:
It sounded like an answer to me, essentially what he [Andre Jute] suggested was that
you try it both with DC, and then with AC and choose the one that sounds
best to you.


Poopie see the light:
Yes that's how I'd do it too !


So the sequence is
1. Jute explains everything.
2. Poopie tries to crash the conversation by claiming Jute didn't.
3. Byrns explains to Poopie what Jute said.
4. Poopie shouts out his agreement. "Yes that's how I'd do it too !"
5. The cock crows three times -- but Poopie has beaten the cock by
denying he ever said:"Yes that's how I'd do it too !"
6. Intermission while onlookers rolls on the floor laughing out loud.
7. To top it all, Poopie Numbnuts then asks earnestly, just like he is
in the converesation:
How about yours ? [Thoughts that is.]


I can understand why the morons don't want Poopie. He'll give them a
bad name.

Andre Jute
The trouble with most people is not what they don't know, but what they
know for certain that isn't true. ---Mark Twain

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Default KISS Amp 300B Ultrafi finalized; circuit updated

In article om, Andre
Jute writes

flipper wrote:
Andre Jute wrote:

You do know that DC filaments on DHT sound like ****, don't you

I, too, would like to hear that explained.


You build tube amps to have the tone quality under your own control.
Most audiophiles arrived there by observing that silicon amps do not
faithfully reproduce the experience of the concert hall.


Do many posters here go to concert halls all that much?. They rarely
sound like what you'd want to hear at home...
--
Tony Sayer

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Default KISS Amp 300B Ultrafi finalized; circuit updated


Eeyore wrote:
Andre Jute wrote:

John Byrns wrote:

I suspect you are actually looking for an explanation of the physics that
make AC heating sound better than DC heating, but the important thing is
the sound.


I can't see why Poopie should need the physics explained to him. He
claims to be an engineering graduate of the University of London.
Surely, he should be explaining the physics to us, rather than the
other way round.


It was discussed in some reasonable depth here quite recently in fact.


Well then, Poopie, you can start work by offering us a summary. You
don't even have to do any work of your own.

And one has to wonder if Poopie is blind to have missed the following
extended explanation of the points on which I make my decision between
AC and DC filaments


Your 'extended explanation' was no more than plain waffle.


Then why did you shout "Eureka!" and "I've seen the light!" after John
Byrns explained in soundbite form what I said? Here it is:

Jute:
You build tube amps to have the tone quality under your own control.
Most audiophiles arrived there by observing that silicon amps do not
faithfully reproduce the experience of the concert hall.


Poopie tries to be smart and cuts away everything else Jute said, then
lies:
Absence of any answer noted.


Byrns:
It sounded like an answer to me, essentially what he [Andre Jute] suggested was that
you try it both with DC, and then with AC and choose the one that sounds
best to you.


Poopie sees the light:
Yes that's how I'd do it too !


So the sequence is
1. Jute explains everything.
2. Poopie tries to crash the conversation by claiming Jute didn't.
3. Byrns explains to Poopie what Jute said.
4. Poopie shouts out his agreement. "Yes that's how I'd do it too !"
5. Even after this revelation on the road to Damascus that Jute gets
it spot on, Poopie is still so thick that he tries to claim that "Yes
that's how I'd do it too!" can be reconciled with "Your 'extended
explanation' was no more than plain waffle." about precisely the same
materiak!

Poor Poopie!

Andre Jute

Andre Jute
Our legislators managed to criminalize fox-hunting and smoking; when
they will get off their collective fat backside and criminalize
negative feedback? It is clearly consumed only by thickoes like Graham
"Poopie" Stevenson.

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Andre Jute wrote:

What happenened was that John Byrns kindly explained *my* thoughts on
the matter


Because you're incapable of doing it yourself I note.

Graham

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