Hi RATs,
I've been hearing lately that the current production Chinese
tubes (ShuGuang) are actually quite good nowadays, and not
the cr*p they used to be a couple of years back.
Does any one have any actual hands on experience with this
(and not here say comments)?
I've been offered current productions Chinese tubes for a
decent price, but if they're still not OK, then I have no
interest of course.

--
Kind regards,
Dr.Tube,
www.DrTube.com
www.DrTube.nl

Dr.Tube wrote

I've been offered current productions Chinese tubes for a
decent price, but if they're still not OK, then I have no
interest of course.

Hello, Dr.

Can you tell us exactly what tube is being offered for
what price so that people can get better idea.

I bought a couple of Penta Lab KT-88 back in 1996, but that
was because it was $15 a peice. It looked like, shaped like,
and gettered like KT-88.

Atsunori

"Dr.Tube" wrote:

Hi RATs,
I've been hearing lately that the current production Chinese
tubes (ShuGuang) are actually quite good nowadays, and not
the cr*p they used to be a couple of years back.
Does any one have any actual hands on experience with this
(and not here say comments)?

I don't have the experience but Lord Valve would have a little more to
say.


I've been offered current productions Chinese tubes for a
decent price, but if they're still not OK, then I have no
interest of course.

Why not be a realist, and buy a few and try to use them,
see how long they last, how stable the bias is, see what the distortion
is like
new, then 6mths later, then test for grid current at idle over 6mths,
whether they'll take a couple
of "red hot anode events" without failing, and get back to us.

I am not insinuating chinese tubes are good or bad or anything else;
I don't have reason to buy any, but sometimes the real truth can only be
found
by a fair trial.

Patrick Turner.





--
Kind regards,
Dr.Tube,
www.DrTube.com
www.DrTube.nl

Yo, Tube,

I use Chinese tubes daily in amps on for 14-16hrs. I have no complaints
about the quality or the longevity. Besides a couple of tubes that I
destroyed in tests to determine how much voltage and current they can
really carry, I've had one Chinese 300B break in about ten years, and
it may be that it ran out of bias adjustment on the pot, a circuit
problem really rather than a reliability problem. (The tube anyway had
about 7000 hours on it, a good run for sixty bucks...) I've never had a
Western Electric 300B break. But the point is: If a Chinese tube costs
a tenth of the price of an American one, and sounds 95% as good, surely
you can buy a few to test. I would have no problem selling Chinese 300B
on, if I were in the tube business (I don't sell tubes and any amp I
build for sale has WE and Mullard tubes because people expect it for
that much money). I also have satisfactory experience of Chinese EL34,
6SN7 equivalent, EF86, 5881, and pseudo KT66 (which I assume are
probably some kind of beefed-up 6L6; they're certainly not the same
size as the gennie GE item). The only Chinese tube I ever had bad luck
with was the GZ34 equivalent, which was nowhere near the Mullard spec,
and didn't last if pushed at all (I acquired a lifetime stock of NOS
milspec GZ37, 5R4 and 5U4 rectifiers instead). Those poor quality GZ34
were ten or twelve years ago; the situation may be better now. At that
time there were also Russian tubes being sold as GZ34 which were really
5Z3 (if you were lucky) or sometimes even the far less capable 5Z4;
these Russian tubes were even crappier than the Chinese.

In fact, some of the best-sounding 300B I ever heard were Chinese and
came in killer-matched quads from Triode Supply Japan for their
exemplary Miyabe amp. I also had a good set or two from Koji at Eifel
in Tokyo. Of course, if you are selling on tubes, to match the
standards of the more obsessive Japanese vendors (the only kind of
people I like dealing with), you should build some test-and-trash
margin into your pricing. (1)

HTH.

Andre Jute

(1) Your friend Lord Valve will tell you how much. Heh-heh!


Dr.Tube wrote:
Hi RATs,
I've been hearing lately that the current production Chinese
tubes (ShuGuang) are actually quite good nowadays, and not
the cr*p they used to be a couple of years back.
Does any one have any actual hands on experience with this
(and not here say comments)?
I've been offered current productions Chinese tubes for a
decent price, but if they're still not OK, then I have no
interest of course.

--
Kind regards,
Dr.Tube,
www.DrTube.com
www.DrTube.nl

The Russian tube that gave the most trouble IMO was a "6L6" that was
really a domestic type designed to be between a 6V6 and 6L6. If
operated within design parms it was a fine tube, but of course in
Fender guitar amps where the 6L6 was run over design limit....it died
promptly.

The problem with Chinese tubes is that there isn't one Chinese 300B or
6SN7, there are at any given time a bunch. Some are okay and some are
not. There are a bunch of Chinese tube plants and they operate
autonomously. There is no traceability and QA is a spur of the moment
thing.

If this is a reply to my letter, or a comment on it, you should quote
my letter or at least some relevant passage from it.

Bret Ludwig wrote:
The Russian tube that gave the most trouble IMO was a "6L6" that was
really a domestic type designed to be between a 6V6 and 6L6. If
operated within design parms it was a fine tube, but of course in
Fender guitar amps where the 6L6 was run over design limit....it died
promptly.

If the Fender was already running the 6L6 overspec, you can hardly
blame the Russian tube for not surviving. There are other Russian
tubes, some of them currently listed by a reputable Canadian surplus
dealeer, which are overspec even to 6L6GC yet plugs straight in. Ever
hear of caveat emptor, Bret? It means Buyer beware. It means, Inform
yourself before you plug the tube in.

The problem with Chinese tubes is that there isn't one Chinese 300B or
6SN7, there are at any given time a bunch. Some are okay and some are
not. There are a bunch of Chinese tube plants and they operate
autonomously.

Gee, ****, your double standards are showing, sonny. If anyone told
American entrepreneurs that they *must* make a standard item the way
someone (who? the government? -- that's what the Chinese are trying to
escape, man) tells them to, you'd never hear the end of their shouting
about their constitutional rights.

As for the variety of Chinese tubes, so what? Grist to the mill, I say.
Take a bunch of different 300B from different factories, and from
different designs and quality levels within the same factory, and you
have a sound spectrum. Variety is the spice of life.

Your grasp of tube history is seriously amiss.Let's stick to the
example of the 300B. Whatever makes you think there was ever only one
300B? Actually, there was only one WE300B, because they held the
patent. All others were workalikes, the best workalike being made by
STC in England who called it the 4300. Today any so-called Chinese 300B
is in fact a copy of the STC 4300.

But why should the Chinese, uniquely, stick to making a chinese copy of
WE300B, as you seem to demand? Because they are a bunch of jumped up
peasants, not as good as Americans? Nobody else made a straight chinese
copy back then, nobody else does now, so why should the Chinese. Cetron
and STC back then made their own workalikes, and today Vaic and Kron
make widely varying tubes that they all offer as direct but somehow
enhanced versions of the 300B. In addition some of those Chinese
workalikesbutbetter are fine tubes in their own right. As are the
Russian and Slovakian versions, however close or distant they are from
the WE300B. I remember that the first thing I thought when I took the
laboratory sample of the first JJ 300B (well, actually, it was still
marked Tesla) out of the box was "Jesus, it must be half as big again
as the WE. I wonder if it will fit under the covers." And I remember
that the first time I plugged in a pair of Vaic/KR300 of the blue
glass, flat top variety, I grinned and said, "See, I was always right
about the 300B sounding even better if only it could be made to wear a
little more current."

There is no traceability and QA is a spur of the moment
thing.

We precisely don't want too much traceability, in the sense of a
Pentagon specification bully standing over the production line, because
it stultifies invention and modification, either planned or
serendipitous. I'd rather have the multiplicity of sounds that plug
straight into a UX4 socket prepared for a 300B than 100% quality
assurance, thank you very much. Tube hi-fi is a hobby and an
entertainment, not an activity of the Hitler Youth.

As for QA, you aren't paying attention. I actually use Chinese tubes
and said so in my letter to Dr Tube. I'm very demanding but I have no
quality problems with Chinese tubes. If *you* have doubts about Chinese
tube quality, you have the remedy in your own hands: don't buy Chinese
when you can pay ten times the price for NOS American tubes. Just don't
come whine about it on RAT because someone is sure to point out that
you could have had a perfectly reliable Chinese tube for a tenth of the
money.

Andre Jute
Amused by erstwhile enthusiastic free traders running for protection
before adverse trade balances

"If this is a reply to my letter, or a comment on it, you should quote
my letter or at least some relevant passage from it."

Bandwidth, and comprehensibility, mitigate against further quoting.




Andre, your knowledge of manufacturing and engineering history is
abysmal, just like your bizarre street rod building book.

And your reading comprehension is on the same order.

My "beef" isn't with the Russians who manufactured the abovementioned
tube, but with American vendors who imported it and sold it as a 6L6.
It would work okay in a console radio originally designed for the metal
6L6, but it would not survive modern 6L6 guitar amp service and it
pulled too much heater current to be safe in a lot of old 6V6
applications. But they could get a lot of them cheaply and so a 6L6 it
became.


A tube type cannot be patented. Specific construction features of
course can, but there were none such specific to the WE 300A/B (they
are exactly the same tube except they fit a different WE twist lock
socket-in conventional four pin sockets they interchange exactly.) And
even if there were, the patent would have run out in the 1960's.

A thing is what it is-A equals A. If the device is labeled 300B, and
is a glass envelope four pin based vacuum tube, a buyer will logically
anticipate it will work in a highly similar manner to other 300B tubes.
If you wish to make a tube that's similar but differs in important
respects, it should have a different device number.

If you are intending to build a _high fidelity_ amplifier, there
should NOT be a multiplicity of devices that give a multiplicity of
sounds that plug in to the tube sockets. In a musical instrument amp or
other device which is ostensibly sought not so much for amplification
as for signal modification, that might be OK. But it still should be
marked, designated and marketed accordingly.

And finally I have never been a believer or adherent in unilateral or
unrestricted "free trade". I am not now, have not been in the past, and
will never be such an advocate. When the corporations of one nation can
disinvest from their own nation with impunity and build factories in
what were third world countries specifically to dodge the laws and
standards of their host nation, their operations should be rendered
essentially uneconomic by fiat.

Bret Ludwig wrote:

Andre, your knowledge of manufacturing and engineering history is
abysmal, just like your bizarre street rod building book.

Oh dear. The people who built original cars from the ground up out of
my book and are happily driving them will be horrified to hear it is a
"street rod building book". Some of them are Americans who moved to
Europe to escape the rednecks. You clearly have never seen a copy of
the book you try to condemn. It is a book about building sports cars on
old Bentley chasses, about building lightweight Index of Performance
specials, about building ultrafast offroaders. I didn't write it for
hotrodders, whose thing is buying parts off the shelf to build a car
that has been built a million times before. I wrote it for people who
start from first principles. It comes as no surprise that to a crude
redneck like you my book seems bizarre and incomprehensible. Of course
it does; that is its strength.

It doesn't speak well for your intelligence, Ludwig, or your
comprehension of your mother tongue, that you bought (or stole) my book
if your intention was to learn to bolt together a standard American
hotrod. You must be truly stupid if you buy a book with a Bentley
special on the front cover and a Marcos on the back cover as a guide to
building a Deuce.

That by itself, even without your other stupidities, makes you a worse
idiot than those quarterwits assaulting Stereophile for not being what
they want it to be (and why should it pander to them?--they're a
minority of fools) to demand that my book, clearly aimed at
sophisticated one-off designers, should pander to your demands for a
book to tell you how to bolt together stock parts into a copycat
hotrod, or how to customize whatever boremobile you drive. Yech!

Your wilful error is indicative of what I object to about you, your
"street corner in the hood", Little-America, belief that you are the
centre of the universe and everything in that universe must proceed
from the hub of your interests, for instance your blithe, risible
assumption that all books about building cars must be about hot rods.
How thickly insular can even a redneck become?

And your reading comprehension is on the same order.

I must apologize for that. English isn't my first language.

(In case everyone else is too courteous to point it out to you, that's
sarcasm. I'm sending you up.)

A tube type cannot be patented.

Etcetera. It isn't worth explaining to such a literal-minded moron.

If you are intending to build a _high fidelity_ amplifier, there
should NOT be a multiplicity of devices that give a multiplicity of
sounds that plug in to the tube sockets.

You mean there should be only one tube per socket? Perhaps we should
call theoneandonlypermitted tube Koba. That was Stalin's nickname at
the seminary. He was also called Soso, which is what we can expect from
the sound of any tube specced and enforced by the Ludwig Dictatorship
of Sound.

You're making the common mistake of assuming that I agree with the
lowest common denominator of engineering hanger-on in audio that THD
measurements predict which amps will sound good. I don't; I consider
any faith in that belief a sign of terminal degeneracy of the brain,
probably induced by syphilis, so that eventually the sufferers of this
belief go stark raving mad (see Stereophile thread for multiple
examples).

In a musical instrument amp or
other device which is ostensibly sought not so much for amplification
as for signal modification, that might be OK. But it still should be
marked, designated and marketed accordingly.

We think more subtly here on RAT, and build more subtle amps. AGA is a
good place for guitar amp builders.

And finally I have never been a believer or adherent in unilateral or
unrestricted "free trade". I am not now, have not been in the past, and
will never be such an advocate. When the corporations of one nation can
disinvest from their own nation with impunity and build factories in
what were third world countries specifically to dodge the laws and
standards of their host nation, their operations should be rendered
essentially uneconomic by fiat.

Add economics to the list of subjects on which you display
self-lacerating ignorance. But, again, I can't be bothered to explain
to you what an opportunity to increase America's influence, wealth and
wellbeing the opening up of China is. Nixon and Kissinger were the two
most brilliant Americans of the 20th century, and opening up China was
the most briliiant thing they did. But Bret Ludwig, the street corner
political philosopher, wants Americans to puddle steel so they can
build more aircraft carriers!

Andre Jute

Andre Jute wrote:

Bret Ludwig wrote:

Andre, your knowledge of manufacturing and engineering history is
abysmal, just like your bizarre street rod building book.

Oh dear. The people who built original cars from the ground up out of
my book and are happily driving them will be horrified to hear it is a
"street rod building book". Some of them are Americans who moved to
Europe to escape the rednecks. You clearly have never seen a copy of
the book you try to condemn. It is a book about building sports cars on
old Bentley chasses, about building lightweight Index of Performance
specials, about building ultrafast offroaders. I didn't write it for
hotrodders, whose thing is buying parts off the shelf to build a car
that has been built a million times before. I wrote it for people who
start from first principles. It comes as no surprise that to a crude
redneck like you my book seems bizarre and incomprehensible. Of course
it does; that is its strength.

It doesn't speak well for your intelligence, Ludwig, or your
comprehension of your mother tongue, that you bought (or stole) my book
if your intention was to learn to bolt together a standard American
hotrod. You must be truly stupid if you buy a book with a Bentley
special on the front cover and a Marcos on the back cover as a guide to
building a Deuce.

That by itself, even without your other stupidities, makes you a worse
idiot than those quarterwits assaulting Stereophile for not being what
they want it to be (and why should it pander to them?--they're a
minority of fools) to demand that my book, clearly aimed at
sophisticated one-off designers, should pander to your demands for a
book to tell you how to bolt together stock parts into a copycat
hotrod, or how to customize whatever boremobile you drive. Yech!

Your wilful error is indicative of what I object to about you, your
"street corner in the hood", Little-America, belief that you are the
centre of the universe and everything in that universe must proceed
from the hub of your interests, for instance your blithe, risible
assumption that all books about building cars must be about hot rods.
How thickly insular can even a redneck become?

And your reading comprehension is on the same order.

I must apologize for that. English isn't my first language.

(In case everyone else is too courteous to point it out to you, that's
sarcasm. I'm sending you up.)

A tube type cannot be patented.

Etcetera. It isn't worth explaining to such a literal-minded moron.

If you are intending to build a _high fidelity_ amplifier, there
should NOT be a multiplicity of devices that give a multiplicity of
sounds that plug in to the tube sockets.

You mean there should be only one tube per socket? Perhaps we should
call theoneandonlypermitted tube Koba. That was Stalin's nickname at
the seminary. He was also called Soso, which is what we can expect from
the sound of any tube specced and enforced by the Ludwig Dictatorship
of Sound.

You're making the common mistake of assuming that I agree with the
lowest common denominator of engineering hanger-on in audio that THD
measurements predict which amps will sound good. I don't; I consider
any faith in that belief a sign of terminal degeneracy of the brain,
probably induced by syphilis, so that eventually the sufferers of this
belief go stark raving mad (see Stereophile thread for multiple
examples).

In a musical instrument amp or
other device which is ostensibly sought not so much for amplification
as for signal modification, that might be OK. But it still should be
marked, designated and marketed accordingly.

We think more subtly here on RAT, and build more subtle amps. AGA is a
good place for guitar amp builders.

And finally I have never been a believer or adherent in unilateral or
unrestricted "free trade". I am not now, have not been in the past, and
will never be such an advocate. When the corporations of one nation can
disinvest from their own nation with impunity and build factories in
what were third world countries specifically to dodge the laws and
standards of their host nation, their operations should be rendered
essentially uneconomic by fiat.

Add economics to the list of subjects on which you display
self-lacerating ignorance. But, again, I can't be bothered to explain
to you what an opportunity to increase America's influence, wealth and
wellbeing the opening up of China is. Nixon and Kissinger were the two
most brilliant Americans of the 20th century, and opening up China was
the most briliiant thing they did. But Bret Ludwig, the street corner
political philosopher, wants Americans to puddle steel so they can
build more aircraft carriers!

Andre Jute

No need to apologise for English not being your first language.

Is it Australian you you speak? anyway, seems like you need no lessons from
me.

The chinese demand at present for raw materials for this revolution in
manufacturing
that is occuring is having some odd effects other than causing gross hatred
in the minds of American and Oz workers laid off because the chinese will
work for
$2 per day.
GOSS laminations have risen in price from aud $8 per Kg to $12 due to chinese
demand,
not to mention the rise in fuel price from $1 a litre 18mths ago to $1.30.

But I won't pay $300 for a single WE 300B made in the US by WE workers.

Meanwhile as the chinese GIANT just starts to get busy, their barons of
industry
look to purchase American companies.

Its all too complex for a mere mortal as me to understand.

I just hang about fixin and makin, and hopin to pay the bills.

I wouldn't mind a Bentley with a special body,
but I'd have to get rich first.

Patrick Turner.

I have actually read Andre's book, which to correct his literal-minded
redneck etceteraism, actually is not about street rods in the literal
sense but is a fast overview of homebuilt "specials". Not completely
worthless, but not really all that useful either.

The premise of "opening up to" China was a theory called "constructive
engagement". In fairness to Nixon and Kissinger that may well have been
the original idea, but it was replaced a long time ago-well prior to
Tiananmen Square-by a whorish lust for corporate approbation and
campaign money on the part of US politicians, Dem and GOP alike.
However, a nation that can't make steel is no world power, and we have
no commodity steel left. We have specialty steel, but no commodity
steel. We have no textile industry to speak of. We have no consumer
electronics, except high end audio and very specialized hobby
equipment. We have one air carrier airframe manufacturer and four
general aviation aircraft manufacturers, three of which are in marginal
economic shape and have more people laid off than working. Yet. our
corporate executive total compensation is at an all-time high, even in
adjusted dollars.

War with China might be a blessing in disguise, even with heavy
casualties, as it would certainly require the United States to
re-industrialize. I don't advocate war, but I do advocate that the
United States maintain its primary and secondary industrial status at
any cost-certainly at the cost of the media, entertainmet, and
corporate elite losing their excessively privileged status.

Patrick:"But I won't pay $300 for a single WE 300B (made in the US) by
WE workers. "


I might add, Patrick, I wouldn't either!

But don't think anyone is getting rich in America on a tube production
line. The so-called "new WE" tubes are not really WE products. For one
thing there is no more WE, and Lucent, their successors, have no
interest in manufacturing vacuum tubes. In fact they have little
interest in manufacturing, period. An American con artist persuaded
Lucent into licensing him the WE name and letting him set up a tube
line in the old WE plant in Lee's Summit, MO, using tooling that Lucent
had either not thrown out yet or had in fact dumpstered and had been
salvaged covertly, and hiring a bunch of old women who had worked the
tube line and who would need no retraining. Like Ripoffchardson, it was
a purely exploitative operation. For the tube line Rosie the Riveters
it was a chance to make a few extra bucks and reminisce with their old
friends. When there weren't enough of them rather than train locals he
moved the operation to Huntsville.

I am not against Chinese products per se. I am very much against
Western capital pulling up stakes, going to China, and making their
products with Western technology-developed at Western expense with
Westerners, taxpayer-funded school trained, with no economic penalty. I
think there should be a $2 tax on preamp tubes and $5 on power tubes
imported from China. That would not drastically raise costs to end
users, but it would keep out huge quantities of untested crap tubes and
raise funds for the nuclear ground penetrating warhead we need to
absolutely guarantee we can kill China's Communist leadership if they
invade Taiwan-its true purpose and a good one too.

Patrick Turner wrote:
Andre Jute wrote:

Bret Ludwig wrote:
And your reading comprehension is on the same order.

I must apologize for that. English isn't my first language.

(In case everyone else is too courteous to point it out to you, that's
sarcasm. I'm sending you up.)

Andre Jute

No need to apologise for English not being your first language.

Is it Australian you you speak? anyway, seems like you need no lessons from
me.

Standard English in the received pronunciation. I don't even try to
sound Australian in Australia, or American in America. Everyone
understands BBC-speak. Trivia: According to the BBC, the purest English
in the world is spoken in a couple of Irish private schools. My son
went to one of them but I could never hear that the kids spoke
particularly purely -- in fact their language was as foully littered
with trendy street phrases as that of any other group of kids.

The chinese demand at present for raw materials for this revolution in
manufacturing
that is occuring is having some odd effects other than causing gross hatred
in the minds of American and Oz workers laid off because the chinese will
work for
$2 per day.
GOSS laminations have risen in price from aud $8 per Kg to $12 due to chinese
demand,
not to mention the rise in fuel price from $1 a litre 18mths ago to $1.30.

When the rest of the world forces the Chinese to let their currency
float, their wages will within a few years achieve parity with Taiwan,
Japan and America, in sequence. President Bush has taken the first step
to force the Chinese to revalue their currency.

But I won't pay $300 for a single WE 300B made in the US by WE workers.

900 American dollars plus carriage for a matched pair direct from WE,
according to an invoice in my hand. For that much they throw in a nice
cherrywood box to hold the pair. Mine are complimentary, of course, but
several sets on amps built for others who paid the full price plus my
loading are much appreciated. Over the long term the gennie WE item
proves itself not only sturdy but very listenable. Eventually you
forget the price and grasp the value. It certainly is more than a mere
myth, especially in the sort of very highly developed and matched
system that can bring out that special midrange, and to the ears of of
mature audiophiles who no longer concentrates solely on the extreme
frequencies as the sole measure of goodness. None of the cheaper tubes
have that special mellowness of the gennie WE item.

Meanwhile as the chinese GIANT just starts to get busy, their barons of
industry
look to purchase American companies.

Actually, America has nothing to fear from China; Americans can export
services and knowledge. But Australia, which in Chinese eyes is a food
basket, has plenty to fear from an arrogant and aggressive neighbour so
overpopulated and so unstable. You're right to put your finger on the
scale difference. When the elephant turns over in its sleep, it doesn't
even know the names of the small animals it crushes. The greatest
possible guarantee of Australian safety is to turn the Chinese into
fat, sluggish, secure, wealthy middle citizens soonest, and free trade
is the fastest way to do that.

Its all too complex for a mere mortal as me to understand.

Geopolitics can be fun as long as your seat in the last chopper out is
reserved and, as I used to do when I was an advisor in South America,
guaranteed by holding the pilot's wife and child in an apartment in
Florida the address of which he doesn't know. The middle seat in the
back row is the safest as the engine is between you and bullets from
the ground.

I wouldn't mind a Bentley with a special body,
but I'd have to get rich first.

I built several nice one-off Bentleys for a fifth or so of the price of
a new one. First, persuade your wife that old cars is a cheaper hobby
than keeping mistresses...

Patrick Turner.

Andre Jute
Trick cyclist

Hey, Ludwig:

Now I understand why you don't quote the text you reply to. It is
because you don't want to be held to account for your lies:

You claim my book is for hotrodders. (1)

I tell you it isn't for hotrodders. (2)

You "correct" me to say it isn't for hotrodders.(3)

That's a lie, Ludwig, trying to imply that I said something incorrect.
You told it deliberately and tried to suppress the evidence.

Andre Jute

(1) Bret Ludwig wrote:
Andre, your knowledge of manufacturing and engineering history is
abysmal, just like your bizarre street rod building book.

(2) Andre Jute replied:
Oh dear. The people who built original cars from the ground up out of
my book and are happily driving them will be horrified to hear it is a
"street rod building book". ... It is a book about building sports cars on
old Bentley chasses ...

(3) Bret Ludwig wrote:
I have actually read Andre's book, which to correct his literal-minded
redneck etceteraism, actually is not about street rods in the literal
sense but is a fast overview of homebuilt "specials".

PS That book isn't "a fast overview of homebuilt specials" either, as
you claim. But, frankly, I don't feel like discussing my books with a
fascist who wants to bomb Beijing because he wants to increase the
price of Chinese tubes.

Bret Ludwig wrote:

Patrick:"But I won't pay $300 for a single WE 300B (made in the US) by
WE workers. "

I might add, Patrick, I wouldn't either!

But don't think anyone is getting rich in America on a tube production
line. The so-called "new WE" tubes are not really WE products. For one
thing there is no more WE, and Lucent, their successors, have no
interest in manufacturing vacuum tubes. In fact they have little
interest in manufacturing, period. An American con artist persuaded
Lucent into licensing him the WE name and letting him set up a tube
line in the old WE plant in Lee's Summit, MO, using tooling that Lucent
had either not thrown out yet or had in fact dumpstered and had been
salvaged covertly, and hiring a bunch of old women who had worked the
tube line and who would need no retraining. Like Ripoffchardson, it was
a purely exploitative operation. For the tube line Rosie the Riveters
it was a chance to make a few extra bucks and reminisce with their old
friends. When there weren't enough of them rather than train locals he
moved the operation to Huntsville.

I am not against Chinese products per se. I am very much against
Western capital pulling up stakes, going to China, and making their
products with Western technology-developed at Western expense with
Westerners, taxpayer-funded school trained, with no economic penalty. I
think there should be a $2 tax on preamp tubes and $5 on power tubes
imported from China. That would not drastically raise costs to end
users, but it would keep out huge quantities of untested crap tubes and
raise funds for the nuclear ground penetrating warhead we need to
absolutely guarantee we can kill China's Communist leadership if they
invade Taiwan-its true purpose and a good one too.

Well, that last paragraph depicts a fascinating train of thought but
I am not sure I coulds agree with much of it.

Fact of the matter is that once one dude starts making joggers for almost
zip
expense in asia and continues to sell them in the US for prices determined
by
US production costs, then all the dudes drift towards asian labour,
and finally the price eventually falls for such items because they very
slowly
start to compete with each other on price.
There is no going back, and soon all our clothing and footware is made in
asia,
and if it wasn't it'd all cost 4 times what it does.
Meanwhile the factory workers in the asian sweatshops would have to save up

for a week to just buy the shoelaces of the joggers.
Something's wrong of course; but there will not be a war over the worker's
global
inequalities though. The chinese govt might be communist, but that doesn't
mean it champion's workers rights. Their govt won't even let ppl
get on the Net to talk about all this ****.

But if the wages and conditions in asia were equal in real terms to wages
and conditions
in the US, then it wouldn't matter where the factories were, the price of
goods would be the same
everywhere.
But productivity is higher in asia. That just means they work for a
pittance.
The capitalists don't mind employing communists to make things.

I think one can accurately state that the US has a sufficient arsenal of
weapons of mass destruction
to do whatever it damn well likes to any country many times over without
reying
on a surcharge of a few bucks on preamp and power amp tubes.

After WW2, Japan and West Germany became very powerful.
By 1955, Germany was making more steel than Britain, despite the
bombing of their factories.
China looks set to keep on increasing many times over its steel production,

( and let's not forget India ) and there would be no point in continuing
"western nation productions" because the asian steel will be so much
cheaper,
and the asians are so happy to deal with us, dealing and trading is far
more to their
liking than having wars, even though we feel guilty about buying their
cheap rotten crap knowing it put our uncle out of work.

Having wars to kill a lotta people and keep the power in western hands
won't solve anything.
China knows there is more to be gained by working and trading rather than
fighting,
so let's leave em to it, and methinks we will never need bunker busters, so

let's retire about 75% of the armaments industry and get them to make
other things, like non polluting energy sources so we can ameliorate the
greenhouse effect
which looks to have a far far greater effect than the few terrorists
everyone is screaming about.
While we are at it we should be prepared to share all our research for FREE
to anyone who wants it
so they won't repeat our mistakes.
Of course Bin Laden would like to see the price of oil rise to 4 times what
it is because he says
its the only commodity that hasn't risen much since 1975.
He feels ripped off by the west, which is dependant on m.east oil.
It makes some folks unhappy to be ripped, so they bomb a few places to send
a message.
I guess the spare retired hoards of US arms makers wouldn't be much good at
negotiating
a deal that Bin Laden and his friends couldn't refuse.
Part of the deal would have to be to provide work for all the idle arabs
who otherwise
join terrorist organizations to make some damn thing change.


But anyway, it appears the war in Iraq for the oil is going to be paid for
by the west
in the form of raised gas prices, here its gone from $1 a litre to $1.30 in
about 18mths.

Ain't nothin like dealin an wheelin and democrazee.

Patrick Turner.

Andre Jute wrote:

Patrick Turner wrote:
Andre Jute wrote:

Bret Ludwig wrote:
And your reading comprehension is on the same order.

I must apologize for that. English isn't my first language.

(In case everyone else is too courteous to point it out to you, that's
sarcasm. I'm sending you up.)

Andre Jute

No need to apologise for English not being your first language.

Is it Australian you you speak? anyway, seems like you need no lessons from
me.

Standard English in the received pronunciation. I don't even try to
sound Australian in Australia, or American in America. Everyone
understands BBC-speak. Trivia: According to the BBC, the purest English
in the world is spoken in a couple of Irish private schools. My son
went to one of them but I could never hear that the kids spoke
particularly purely -- in fact their language was as foully littered
with trendy street phrases as that of any other group of kids.

The chinese demand at present for raw materials for this revolution in
manufacturing
that is occuring is having some odd effects other than causing gross hatred
in the minds of American and Oz workers laid off because the chinese will
work for
$2 per day.
GOSS laminations have risen in price from aud $8 per Kg to $12 due to chinese
demand,
not to mention the rise in fuel price from $1 a litre 18mths ago to $1.30.

When the rest of the world forces the Chinese to let their currency
float, their wages will within a few years achieve parity with Taiwan,
Japan and America, in sequence. President Bush has taken the first step
to force the Chinese to revalue their currency.

These things I am not sure of. Maybe western nations will suffer a sinking wage
while other wages float upwards.......
Meanwhile the rich will get richer, and not give a damn about the poor getting
poorer....



But I won't pay $300 for a single WE 300B made in the US by WE workers.

900 American dollars plus carriage for a matched pair direct from WE,
according to an invoice in my hand. For that much they throw in a nice
cherrywood box to hold the pair. Mine are complimentary, of course, but
several sets on amps built for others who paid the full price plus my
loading are much appreciated. Over the long term the gennie WE item
proves itself not only sturdy but very listenable. Eventually you
forget the price and grasp the value. It certainly is more than a mere
myth, especially in the sort of very highly developed and matched
system that can bring out that special midrange, and to the ears of of
mature audiophiles who no longer concentrates solely on the extreme
frequencies as the sole measure of goodness. None of the cheaper tubes
have that special mellowness of the gennie WE item.

I cannot argue with a sylable here. I have never experienced the WE magic
and i know of nobody who has.

But I keep thinking of the slavish devotion to the 300B as the
be all and end all of triodes, and this all originated from theatre sound amps.
And theatre sound was never all that marvellous, and still isn't, even with
SS and surround....

Anyway, I have heard chinese 300B blow away modern SS amps of 10 times the power.
Then I have heard the Alesa Vaic made 300Bs that sounded rather decent to me.
Now there are Emission Labs....

I did try to coax EI to make a new production octal based triode
about the same size as a KT90 and with Pda = 55 watts but that led only
to to a dreamy discussion with a drunken engineer, who tried to tell me they
already planned a 400B, but I ain't seen no 400B yet.....





Meanwhile as the chinese GIANT just starts to get busy, their barons of
industry
look to purchase American companies.

Actually, America has nothing to fear from China; Americans can export
services and knowledge. But Australia, which in Chinese eyes is a food
basket, has plenty to fear from an arrogant and aggressive neighbour so
overpopulated and so unstable. You're right to put your finger on the
scale difference. When the elephant turns over in its sleep, it doesn't
even know the names of the small animals it crushes. The greatest
possible guarantee of Australian safety is to turn the Chinese into
fat, sluggish, secure, wealthy middle citizens soonest, and free trade
is the fastest way to do that.

Ah, so Americanization of the Chinese should do the trick you reckon.
Let's get Indonesians all round and fat, and also the Indians while we are at it.

I have this fear that the planet just couldn't sustain another 3 billion who
are overweight because they have so much.
That'll still leave 2 billion more doing it tough, and finally in 50 years
when all 9 billion of us have an average weight of an American
and two cars the garage, things will be alright.

And porcine flight will be possible.

But by the time all this becomes a serious problem, and surely it must, I'll be
dead.
Someone elses's problem.


Its all too complex for a mere mortal as me to understand.

Geopolitics can be fun as long as your seat in the last chopper out is
reserved and, as I used to do when I was an advisor in South America,
guaranteed by holding the pilot's wife and child in an apartment in
Florida the address of which he doesn't know. The middle seat in the
back row is the safest as the engine is between you and bullets from
the ground.

I wouldn't mind a Bentley with a special body,
but I'd have to get rich first.

I built several nice one-off Bentleys for a fifth or so of the price of
a new one. First, persuade your wife that old cars is a cheaper hobby
than keeping mistresses...

I am disgustingly minimalist. Not a wife within cooee,
mistresses won't have me, and I am happy with a 1987 Ford Laser.
I play chess on Saturday nights.
I don't care what the chinese or americans might do, or might not do.
I have not the slightest control over them.

Patrick Turner.



Patrick Turner.

Andre Jute
Trick cyclist

On Mon, 29 Aug 2005 01:18:50 GMT, Patrick Turner
wrote:

But by the time all this becomes a serious problem,
and surely it must, I'll be dead.
Someone else's problem.

SEP's are the modern postmodernism. How's that for
newsgroup pomo bullspeak?

But seriously, I'd agree with both of ya. America
is at war with China, and only China knows about it.

'Course, a very cool Chinese guy wrote a book about
it several millenia ago, _The Art of War_, which
is ignored today at one's peril.

America is run by figureheads of properly funded
corporate and religious interests (including an
Australian, so don't be smug) and China is run
by figureheads of properly funded corporate and
military interests. The difference between either
one and, for example, Chad, or some other pathetic
kleptocracy, is just a matter of time.

But maybe I'm wrong,
(And don't count on being dead; Moore's Law....)
Good fortune to us all,

Chris Hornbeck
"Fa yeung nin wa" -Wong KarWai

Chris Hornbeck wrote:
America is run by figureheads of properly funded
corporate and religious interests (including an
Australian, so don't be smug) and China is run
by figureheads of properly funded corporate and
military interests. The difference between either
one and, for example, Chad, or some other pathetic
kleptocracy, is just a matter of time.

Chris Hornbeck
"Fa yeung nin wa" -Wong KarWai

If you mean Murdoch, I've worked for him. He's all right. He just wants
to make money. I'd be a lot more worried if a guy with his drive were
an ideologue.

I've been to Chad and elsewhere in Africa. I doubt that any nation,
once industrialized, can sink that low. But conditions in Africa are
not improving, they are worsening. Here is a par from a private letter
I wrote a couple of days ago:

****

While I was in the bike workshop a guy came in with his two little
girls. He's a surveyor in Borneo and Africa and Louisiana and Latin
America. He's just back from Nigeria. Right in centre of Abidjan he has
to be accompanied by two men with AK47s. He says, "In Nigeria the
criminals have more armed outriders than the prime minister. At least
it is better than Jo'burg. You don't go into the centre of Johannesburg
even in daylight now, not if you want to live you don't. Even the drug
dealers are trying to move out to a less dangerous environment."

****

Johannesburg, the last time I was there (35 years ago) was a place
where a group of teenage girls could go to the cinema in the centre of
the city without fear of even being lewdly accosted. If on my way to
the skating rink I saw a girl or two standing at a busstop with skates
hanging by their laces over their shoulders, I would stop to offer them
a lift; I cannot remember any who refused the ride. The biggest
excitement was on Sunday afternoons when people would sit in their cars
and watch the Little Jews and the Little Lebanese, rival gangs, fight
on the town hall steps. Knives and other metal implements were
forbidden.

How innocent we all once were.

Andre Jute

How innocent we all once were.

Andre Jute


I'm not convinced you EVER were innocent!


;-)

On 28 Aug 2005 21:12:23 -0700, "Andre Jute" wrote:

Louisiana

At dawn local time, Katrina is predicted to put a 28 foot
storm surge over the 13 foot levies of N'orleans. Not a
happy time here.

How innocent we all once were.

Yup.
Enough hours north to easily get some sleep,

Chris Hornbeck
"What I love about Jean-Luc Godard is that he is honest, smart,
and has no humility." -butterfinger, reviewing _Peirrot le fou_, 1965

Patrick Turner said:

But I keep thinking of the slavish devotion to the 300B as the
be all and end all of triodes, and this all originated from theatre sound amps.
And theatre sound was never all that marvellous, and still isn't, even with
SS and surround....


I just finished a stereo amp with 2 x 2A3 in push pull, with salvaged
Unitran transformers from the '60s.
Marvellous sound, and if I ever fall prey to the PMPO virus, I just
add 2 more in PPP configuration.

BTW they're recent Chinese production 2A3s, and Im very happy with how
they sound and keep their bias constant.

Does anyone know why 2A3s sound so much better than 6B4Gs, which ought
to be the same tube but with a 6 V filament?
I originally úsed a PT intended for use of 6B4Gs, with 6.3V and 1A
they're far more easy to use.
I compared Ultron 6B4Gs with the Chinese 2A3s, and decided to use the
latter ones. Even had a special tranny made for the 4 x 2.5V
windings..

Has it something to do with the length of the filament cathode, and
the larger voltage sag across it?


I am disgustingly minimalist. Not a wife within cooee,
mistresses won't have me, and I am happy with a 1987 Ford Laser.
I play chess on Saturday nights.


I'm perfectly happy with my 1987 Citroen CX, and I don't even play
chess on saturdays (instead I fix the bloody car :-) )


I don't care what the chinese or americans might do, or might not do.
I have not the slightest control over them.


While it might be true that you or I don't have any influence, it
surely is wise to keep an eye on the news.

--

"Audio as a serious hobby is going down the tubes."
- Howard Ferstler, 25/4/2005

Patrick Turner wrote:
snip
Fact of the matter is that once one dude starts making joggers for almost
zip
expense in asia and continues to sell them in the US for prices determined
by
US production costs, then all the dudes drift towards asian labour,
and finally the price eventually falls for such items because they very
slowly
start to compete with each other on price.
There is no going back, and soon all our clothing and footware is made in
asia,
and if it wasn't it'd all cost 4 times what it does.
Meanwhile the factory workers in the asian sweatshops would have to save up

for a week to just buy the shoelaces of the joggers.

The exceedingly cheap labor isn't the whole story. The Chinese plants
can be run with no concern for Western notions of worker safety, labor
relations, environmental pollution or any of the myriad concern First
World plants must deal with.


Something's wrong of course; but there will not be a war over the worker's
global
inequalities though. The chinese govt might be communist, but that doesn't
mean it champion's workers rights. Their govt won't even let ppl
get on the Net to talk about all this ****.

But if the wages and conditions in asia were equal in real terms to wages
and conditions
in the US, then it wouldn't matter where the factories were, the price of
goods would be the same
everywhere.
But productivity is higher in asia. That just means they work for a
pittance.
The capitalists don't mind employing communists to make things.

Absolute productivity is lower in China, and indeed most of Asia
(Japan being a big exception) because there is nowhere near the level
of capital investment, on the whole. Things get made on an ad hoc basis
in many small shops, often for only one run, and levels of skill in
toolmaking are far below Western levels (again, on the whole.)

However, with no wages to speak of and no restrictive legislative
compliance the overall costs become low enough relative productivity is
excellent.

The vaunted equalizing of costs from floating the currency and other
measures is ridiculous: it might well double or treble labor costs, but
they are still inconsequential.

Only when Chinese society runs roughly along the lines of Western
society will things change, and I do not look for that to ever happen,
any more than for Westerners to adopt Chinese ways. Left to its own
devices, Chinese society would not be a problem in this regard: only
with the leverage of state corporatist government-industry alliance is
it a problem.

A couple of disgruntlebunnies have accused me of "racism": indeed, I
have posted to various newsgroups some things that are somewhat
politically incorrect, but careful reading-as Mr. Jute has over decades
proven incapable of!- will establish that I have little regard for
racialism per se. I do believe that certain people on the racial right
have and continue to state excellent points-as, more saliently, have
others who are definitely not white racialists, or even white-and that
if sufficiently cornered and provoked, if people see racial nationalism
as the only alternative to state corporatism (as indeed Weimar Germans
did) things could go that way again-and with similarly poor results.

Bret Ludwig wrote:

Patrick Turner wrote:
snip
Fact of the matter is that once one dude starts making joggers for almost
zip
expense in asia and continues to sell them in the US for prices determined
by
US production costs, then all the dudes drift towards asian labour,
and finally the price eventually falls for such items because they very
slowly
start to compete with each other on price.
There is no going back, and soon all our clothing and footware is made in
asia,
and if it wasn't it'd all cost 4 times what it does.
Meanwhile the factory workers in the asian sweatshops would have to save up

for a week to just buy the shoelaces of the joggers.

The exceedingly cheap labor isn't the whole story. The Chinese plants
can be run with no concern for Western notions of worker safety, labor
relations, environmental pollution or any of the myriad concern First
World plants must deal with.

Well Bret, what you say echoes the point I was trying to
make about asian industry worker conditions.



Something's wrong of course; but there will not be a war over the worker's
global
inequalities though. The chinese govt might be communist, but that doesn't
mean it champion's workers rights. Their govt won't even let ppl
get on the Net to talk about all this ****.

But if the wages and conditions in asia were equal in real terms to wages
and conditions
in the US, then it wouldn't matter where the factories were, the price of
goods would be the same
everywhere.
But productivity is higher in asia. That just means they work for a
pittance.
The capitalists don't mind employing communists to make things.

Absolute productivity is lower in China, and indeed most of Asia
(Japan being a big exception) because there is nowhere near the level
of capital investment, on the whole.

Not necessarily.
China is smart to give the teams of girls in the garment industries the latest
sewing machines this making the Indian and Pakistan garment industries
redundant.......

Things get made on an ad hoc basis
in many small shops, often for only one run, and levels of skill in
toolmaking are far below Western levels (again, on the whole.)

However, with no wages to speak of and no restrictive legislative
compliance the overall costs become low enough relative productivity is
excellent.

The chinese worker makes 10 pairs of shoes while the western worker makes one
pair....



The vaunted equalizing of costs from floating the currency and other
measures is ridiculous: it might well double or treble labor costs, but
they are still inconsequential.

if chinese wages rise from $2 per day to $8, maybe it doesn't do much.
Shoes will still be made in china.



Only when Chinese society runs roughly along the lines of Western
society will things change, and I do not look for that to ever happen,
any more than for Westerners to adopt Chinese ways. Left to its own
devices, Chinese society would not be a problem in this regard: only
with the leverage of state corporatist government-industry alliance is
it a problem.

Who knows what will happen long term.
I won't be around.



A couple of disgruntlebunnies have accused me of "racism": indeed, I
have posted to various newsgroups some things that are somewhat
politically incorrect, but careful reading-as Mr. Jute has over decades
proven incapable of!- will establish that I have little regard for
racialism per se. I do believe that certain people on the racial right
have and continue to state excellent points-as, more saliently, have
others who are definitely not white racialists, or even white-and that
if sufficiently cornered and provoked, if people see racial nationalism
as the only alternative to state corporatism (as indeed Weimar Germans
did) things could go that way again-and with similarly poor results.

I can't read crystal balls.

Patrick Turner.

Sander deWaal wrote:

Patrick Turner said:

But I keep thinking of the slavish devotion to the 300B as the
be all and end all of triodes, and this all originated from theatre sound amps.
And theatre sound was never all that marvellous, and still isn't, even with
SS and surround....

I just finished a stereo amp with 2 x 2A3 in push pull, with salvaged
Unitran transformers from the '60s.
Marvellous sound, and if I ever fall prey to the PMPO virus, I just
add 2 more in PPP configuration.

Well I just tested the first channel of a stereo amp with a 2A3 SET in each.

What a marvellous tube the 2A3 is!



BTW they're recent Chinese production 2A3s, and Im very happy with how
they sound and keep their bias constant.

The ones I have been using for my customers's amp are RCA NOS;
He wants to use them for 6kHz to 20kHz with his set of restored
Altec horns he has...



Does anyone know why 2A3s sound so much better than 6B4Gs, which ought
to be the same tube but with a 6 V filament?

I'll maybe know the answer by week's end.


I originally úsed a PT intended for use of 6B4Gs, with 6.3V and 1A
they're far more easy to use.
I compared Ultron 6B4Gs with the Chinese 2A3s, and decided to use the
latter ones. Even had a special tranny made for the 4 x 2.5V
windings..

Has it something to do with the length of the filament cathode, and
the larger voltage sag across it?

I am disgustingly minimalist. Not a wife within cooee,
mistresses won't have me, and I am happy with a 1987 Ford Laser.
I play chess on Saturday nights.

I'm perfectly happy with my 1987 Citroen CX, and I don't even play
chess on saturdays (instead I fix the bloody car :-) )

The smell of French Grease and Oils is what does it eh?




I don't care what the chinese or americans might do, or might not do.
I have not the slightest control over them.

While it might be true that you or I don't have any influence, it
surely is wise to keep an eye on the news.

Yup, keep a full tank of gas.

Dunno where I might drive to if things get really dire,
like WW3 occuring with a lotta nukes and poisenous clouds drifting south.....

Anyways, I've lived nearly 60 years, so if the very worst occured
it won't matter to me very much, I'll jus die like the fukkin rest of em..

Recently I saw a guy die while he played chess.
Croaked real well he did.
No pain or screams, just death, a fade out.

His opponent was a little distraught and he damn well forgot
what that winning move was.

Patrick Turner.




--

"Audio as a serious hobby is going down the tubes."
- Howard Ferstler, 25/4/2005

Patrick Turner said:

Does anyone know why 2A3s sound so much better than 6B4Gs, which ought
to be the same tube but with a 6 V filament?

I'll maybe know the answer by week's end.


Please let us know here, I'm really curious.

--

"Audio as a serious hobby is going down the tubes."
- Howard Ferstler, 25/4/2005

François Yves Le Gal said:


Does anyone know why 2A3s sound so much better than 6B4Gs, which ought
to be the same tube but with a 6 V filament?

With what supply ? AC or DC ? Could very well be an imbalance caused by the
higher voltage used for 6B4G's.


I use DC on the filaments, with a floating supply and bypassed cathode
resistors to ground.

My thoughts would be: the larger potential across the filament causes
the area at the positive side to emit less electrons than the area at
the negative side. Is this correct?

But how can that affect the sound, when the average amount of emitted
electrons stays roughly the same (viz. the cathode current) ?

--

"Audio as a serious hobby is going down the tubes."
- Howard Ferstler, 25/4/2005

Sander deWaal wrote:

Patrick Turner said:

Does anyone know why 2A3s sound so much better than 6B4Gs, which ought
to be the same tube but with a 6 V filament?

I'll maybe know the answer by week's end.

Please let us know here, I'm really curious.

I didn't ask whether 2A3 are better than 6B4g. I don't have any 6B4 to
compare
with the 2A3 using the same circuit, with the same drive amp and
transformers.

Before anyone really could know which s better, the amp topology must be
identical.

But by week's snd I will be able to listen with the 2A3 amps and tell if i
like them.

The test of one channel gives 4 watts into 4 ohms with Hammond opt.

The amps concerned are for powering Altec HF horns from 6 kHz up.
So maybe the guy uses 1/10 of a watt.

Patrick Turner.







--

"Audio as a serious hobby is going down the tubes."
- Howard Ferstler, 25/4/2005

Sander deWaal wrote:

François Yves Le Gal said:

Does anyone know why 2A3s sound so much better than 6B4Gs, which ought
to be the same tube but with a 6 V filament?

With what supply ? AC or DC ? Could very well be an imbalance caused by the
higher voltage used for 6B4G's.

I use DC on the filaments, with a floating supply and bypassed cathode
resistors to ground.

My thoughts would be: the larger potential across the filament causes
the area at the positive side to emit less electrons than the area at
the negative side. Is this correct?

The 2A3 has 2.5V filaments.
The typical Ek for cathode bias is +47V.
So the DC across the filament won't make much difference to the emission.
DC use is quite OK with 2A3 or 300B.

The amps I am working on have a 50ohm pot across the fil with its wiper taken to
the
820ohm Rk and 470uF bypass cap.

I have been able to null out the hum to less than 1mV.
Its a very touchy adjustment with 50 ohms though, and
I think I will strap a pair of 22 ohms from wiper to the
ends of the pot to make the adjustment swing a lot broader.





But how can that affect the sound, when the average amount of emitted
electrons stays roughly the same (viz. the cathode current) ?

I don't think it can.

But we have the eternal mystery of DHT.
Ppl say DHT sound better than IDH.
And they say AC heating in DHT sounds better than DC heating.

I just agree with all of them.

Patrick Turner.



--

"Audio as a serious hobby is going down the tubes."
- Howard Ferstler, 25/4/2005

"François Yves Le Gal" wrote:

On Tue, 30 Aug 2005 22:06:39 +0200, Sander deWaal wrote:

My thoughts would be: the larger potential across the filament causes
the area at the positive side to emit less electrons than the area at
the negative side. Is this correct?

Yes. Furthermore, the DC voltage across the filament is significant when
compared to the bias voltage and can cause imbalance.

Some people advocate split filament DC supplies (say + 2.5, - 2,5 for a 5 V
tube) but I've never tried this approach.

But unless you have a CT filament, its pointless to have two 2.5V supplies.
In a 300B the bias is maybe -65V, I forget now, but its a lot,
and the difference in emission due to a 7% difference in bias applied
to the far ends of the filament is negligible.
The average difference is even less.

One can have a CT DC supply but there is no need.

Patrick Turner.

in article , Sander deWaal at
wrote on 8/30/05 4:06 PM:

François Yves Le Gal said:


Does anyone know why 2A3s sound so much better than 6B4Gs, which ought
to be the same tube but with a 6 V filament?

With what supply ? AC or DC ? Could very well be an imbalance caused by the
higher voltage used for 6B4G's.


I use DC on the filaments, with a floating supply and bypassed cathode
resistors to ground.

My thoughts would be: the larger potential across the filament causes
the area at the positive side to emit less electrons than the area at
the negative side. Is this correct?

But how can that affect the sound, when the average amount of emitted
electrons stays roughly the same (viz. the cathode current) ?


Using DC on the preamp and driver tubes makes sense, but why for the
outputs?

It produces slightly lower noise, but it does mean the filament "wears"
slightly more from one end than the other. The polarity should be
reversed on occasion to compensate for this.

in article , Bret
Ludwig at wrote on 8/30/05 9:17 PM:

It produces slightly lower noise, but it does mean the filament "wears"
slightly more from one end than the other. The polarity should be
reversed on occasion to compensate for this.


Maybe in theory, but show me one commercial product with a DC polarity
reversing switch . . . .

Jon Yaeger said:

Using DC on the preamp and driver tubes makes sense, but why for the
outputs?


The humming with an AC filament supply drove me mad.
Maybe I should have used a 1.25-0-1.25 arrangement, but I didn't.

--

"Audio as a serious hobby is going down the tubes."
- Howard Ferstler, 25/4/2005

Patrick Turner said:

Does anyone know why 2A3s sound so much better than 6B4Gs, which ought
to be the same tube but with a 6 V filament?

I'll maybe know the answer by week's end.

Please let us know here, I'm really curious.

I didn't ask whether 2A3 are better than 6B4g. I don't have any 6B4 to
compare
with the 2A3 using the same circuit, with the same drive amp and
transformers.


Ok, sorry, I misunderstood.


Before anyone really could know which s better, the amp topology must be
identical.


I compared them, the 2A3 have just a certain "something" that the
6B4Gs lack. Don't know how else to put it.


But by week's snd I will be able to listen with the 2A3 amps and tell if i
like them.


You will :-)

--

"Audio as a serious hobby is going down the tubes."
- Howard Ferstler, 25/4/2005

It produces slightly lower noise, but it does mean the filament "wears"
slightly more from one end than the other. The polarity should be
reversed on occasion to compensate for this.

Maybe in theory, but show me one commercial product with a DC polarity
reversing switch . . . .


Show me a commercial product (made since 1963) with DC heated
filamentary tubes!

It's strictly for homebrewers.

On Wed, 31 Aug 2005 19:11:16 +0200, Sander deWaal
wrote:

Using DC on the preamp and driver tubes makes sense, but why for the
outputs?


The humming with an AC filament supply drove me mad.
Maybe I should have used a 1.25-0-1.25 arrangement, but I didn't.

A trimming pot across the filament can *completely*
null any hum from that source, but a more elegant
solution is the signal-grid-injection method advocated
by one of our reticent-but-still-present guiding
lights.

Chris Hornbeck

Chris Hornbeck wrote:

On Wed, 31 Aug 2005 19:11:16 +0200, Sander deWaal
wrote:

Using DC on the preamp and driver tubes makes sense, but why for the
outputs?


The humming with an AC filament supply drove me mad.
Maybe I should have used a 1.25-0-1.25 arrangement, but I didn't.

A trimming pot across the filament can *completely*
null any hum from that source, but a more elegant
solution is the signal-grid-injection method advocated
by one of our reticent-but-still-present guiding
lights.

Chris Hornbeck

Unfortunately Chris, such a nulling technique is imperfect.

Today i got the second channel of a 2A3 amp going that I'm building for
a client, and with no global NFB, and only a nulling pot, I found that it
was impossible
to get a decent null of all the noise.
Lo and behold, after the 50Hz is nulled out, there remained about 1mV of
100
Hz hum even with the grid grounded, and an impecablly filtered B+ rail PS.

This would be intolerable with horns that went down to say 50Hz.

But the 12dB of NFB reduces the hum to less than 0.3mV, and that's as good
as I can do without
resorting to a DC fil supply.

The 4 watts is a very nice sounding 4 watts though....

Patrick Turner.

Patrick, you don't have to put up with the washed-ut sound of DC fils.
To kill the hum, try taking about a 100 ohms 2W resistor back from
each end of the pot to the wiper arm. See my KISS T30 on my site for an
example. If that still doesn't work, take off the reistors and add a
cap from each end of the pot to ground either side of the cathode bias
network to provide a friendly path.

HTH.

Andre Jute
Visit Jute on Amps at http://members.lycos.co.uk/fiultra/
"an unbelievably comprehensive web site" -- Hi-Fi News & Record Review


Patrick Turner wrote:
Chris Hornbeck wrote:

On Wed, 31 Aug 2005 19:11:16 +0200, Sander deWaal
wrote:

Using DC on the preamp and driver tubes makes sense, but why for the
outputs?


The humming with an AC filament supply drove me mad.
Maybe I should have used a 1.25-0-1.25 arrangement, but I didn't.

A trimming pot across the filament can *completely*
null any hum from that source, but a more elegant
solution is the signal-grid-injection method advocated
by one of our reticent-but-still-present guiding
lights.

Chris Hornbeck

Unfortunately Chris, such a nulling technique is imperfect.

Today i got the second channel of a 2A3 amp going that I'm building for
a client, and with no global NFB, and only a nulling pot, I found that it
was impossible
to get a decent null of all the noise.
Lo and behold, after the 50Hz is nulled out, there remained about 1mV of
100
Hz hum even with the grid grounded, and an impecablly filtered B+ rail PS.

This would be intolerable with horns that went down to say 50Hz.

But the 12dB of NFB reduces the hum to less than 0.3mV, and that's as good
as I can do without
resorting to a DC fil supply.

The 4 watts is a very nice sounding 4 watts though....

Patrick Turner.

Andre Jute wrote:

Patrick, you don't have to put up with the washed-ut sound of DC fils.

I don't know if DC fils result in washed out sound, but I will take your point.


To kill the hum, try taking about a 100 ohms 2W resistor back from
each end of the pot to the wiper arm.

The pot used at the 2A3 amp fil is a 50ohm wire wound, which I found was very
touchy to get a null with the hum, and even when the 50Hz was reduced
to almost nothing on the CRO, there was some damned 100Hz still there.
I added 22ohms to each pot end to the wiper, thus reducing the R, and making the
adjust a tiny
but usul amount broader and easier.
There is after all only 1.25Vrms across each 1/2 of the pot.


See my KISS T30 on my site for an
example. If that still doesn't work, take off the reistors and add a
cap from each end of the pot to ground either side of the cathode bias
network to provide a friendly path.

That would mean you are bypassing the 1.25 AC applied to the 2A3 fil to ground.
One wouldn't want to use too big a cap value.
At present I have effectively about 12 ohms each side of the pot wiper to the
filament ends.

I am using some global NFB though, and this reduces the hum and amp noise
to less than the RF and other trash one sees with speakers connected.

I tried out these amps tonight with music, and I have to say its the best 4
watts
I have ever heard; certainly better than a single 6BQ5 for example.

The full power bandwidth is 5Hz to 50 khz; bass is tight, treble is clear,
and there is no indication that it is a little amp of only 4 watts.

I already have 470uF across the Rk = 820 ohms, since I like
good bypassing to avoid the pahse shift when low conventional
values such as 47 uF are used.
I believe the cap micro-dynamic effects dissappear with the larger bypass cap
value.

These amps are good full range amps, but they will be used
with heavy large 8 ohm horn bullet speakers to get from 6kHz upwards
in a triamped system a client is building with my help.
The horns are over 100dB/W/M, so there is oddles of power and amp thd is
less than 0.01% at normal loud levels......

He supplied me with 4.5Kg Hammond OPTs suited for 2A3 with 2.5k load
to 4,8,16 ohms, but I found 5 ohms to be a nice load for 4 watts,
and 8 ohm loads will get around 3 watts max at 1/2 the thd of the 5 ohm loading.

I have a 1/2 12AU7 driving a paralleled 6SN7 to drive the 2A3.

The Hammond OPT was slightly difficult to stabilise since i think
it suffers from too much parasitic shunt C in its windings; its impossible to
get a nice square wave.
But its bottom end is fab, -3Db at 5Hz is from the CR coupings in the amp,
and there was only a hint of saturation at 4Hz as F was reduced in a signal
referenced to clipping at a kHz.

I don't mind 3 amp stages, and I don't think such stages sound worse than having
a high gain
single driver tube to the 2A3.

Patrick Turner.



HTH.

Andre Jute
Visit Jute on Amps at http://members.lycos.co.uk/fiultra/
"an unbelievably comprehensive web site" -- Hi-Fi News & Record Review

Patrick Turner wrote:
Chris Hornbeck wrote:

On Wed, 31 Aug 2005 19:11:16 +0200, Sander deWaal
wrote:

Using DC on the preamp and driver tubes makes sense, but why for the
outputs?


The humming with an AC filament supply drove me mad.
Maybe I should have used a 1.25-0-1.25 arrangement, but I didn't.

A trimming pot across the filament can *completely*
null any hum from that source, but a more elegant
solution is the signal-grid-injection method advocated
by one of our reticent-but-still-present guiding
lights.

Chris Hornbeck

Unfortunately Chris, such a nulling technique is imperfect.

Today i got the second channel of a 2A3 amp going that I'm building for
a client, and with no global NFB, and only a nulling pot, I found that it
was impossible
to get a decent null of all the noise.
Lo and behold, after the 50Hz is nulled out, there remained about 1mV of
100
Hz hum even with the grid grounded, and an impecablly filtered B+ rail PS.

This would be intolerable with horns that went down to say 50Hz.

But the 12dB of NFB reduces the hum to less than 0.3mV, and that's as good
as I can do without
resorting to a DC fil supply.

The 4 watts is a very nice sounding 4 watts though....

Patrick Turner.

On Thu, 01 Sep 2005 09:37:27 GMT, Patrick Turner
wrote:

A trimming pot across the filament can *completely*
null any hum from that source, but a more elegant
solution is the signal-grid-injection method advocated
by one of our reticent-but-still-present guiding
lights.

Unfortunately Chris, such a nulling technique is imperfect.

Today i got the second channel of a 2A3 amp going that I'm building for
a client, and with no global NFB, and only a nulling pot, I found that it
was impossible
to get a decent null of all the noise.
Lo and behold, after the 50Hz is nulled out, there remained about 1mV of
100
Hz hum even with the grid grounded, and an impecablly filtered B+ rail PS.

Trim pot nulling is independent of frequency. If you
have 100 Hz noise, it's pretty much by definition from
the B+ supply.

My first guess is that it's magnetic coupling from
PS iron to the OPT, if you're really, really sure
about your B+ and ground paths etc. And I certainly
trust you to get that stuff right.

Good fortune,

Chris Hornbeck