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Current production Chinese tubes...
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 |
#2
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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 |
#3
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"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 |
#4
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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 |
#5
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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. |
#6
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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 |
#7
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"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. |
#8
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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 |
#9
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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. |
#10
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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. |
#11
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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. |
#12
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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 |
#13
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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. |
#14
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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. |
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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 |
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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 |
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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 |
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How innocent we all once were. Andre Jute I'm not convinced you EVER were innocent! ;-) |
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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 |
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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 |
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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. |
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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. |
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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 |
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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 |
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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 |
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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 |
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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 |
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"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. |
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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. |
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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 . . . . |
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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 |
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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 |
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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. |
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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 |
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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. |
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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. |
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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. |
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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 |
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