| Home |
| Search |
| Today's Posts |
|
#1
|
|||
|
|||
Who owns the classic transformer designs? Is there any reason to wind them today?
wrote:
Turner .... likes to wind his own, which is fine, although I do wish he'd wind the good American kind like Mac, Marantz or Linear Standards, or even Peerless to **** the nut in Philly off. It is an interesting question who now owns the rights to the original design specifications to the likes of Mac, Marantz or Linear Standards, or even Peerless and thus who can reproduce them. When the nut in Philly as you call him was constantly on my ass with his gang, about thirty separate parties wrote to me about the ownership of the great old transformer brand names, including Peerless, that Michael LaFevre of Magnequest claims to own. One of these letters was from the man from whom LaCreepy bought the Magnequest business. The others all offered roughly the same story, some with additional detail. Mike LaFevre claims to own great names like Peerless, and the rights to all their designs. He ferociously attacks anyone who question his claim to own the rights and refuses to publish even specifications that were commonly published when the designs he claims to own were originally made. He has publicly threatened legal action against anyone who reverse engineers e.g. a Peerless transformer whether supplied by him or not. He has publicly refused to supply what his henchmen describe as "troublemakers" for the stated reason that they would test (!) or copy these ancient transformers. He has threatened legal action against anyone publishing newly taken test results of one of his transformers. Thus his concept of what is proprietory information is extraordinarily wide. (This should be interpreted in the light of the known fact that LaFevre's legal knowledge is extraordinarily lacking for someone whose training and experience is in political management, not engineering. For instance, when he tried to sue me, his lawyer told him to grow up.) However, those who contest the Magnequest claim to own the names and all proprietary rights to all the original designs say that all that happened was that person A took a bunch of blueprints out of a dumpster and sold them to person B, person B being Michael LaFevre of what is now Magnequest Transformers, Philadelphia. If that is true all that passed was possibly the rights to reprint the blueprints in LaFevre's hand and even here there is a complication. The story repeatedly told to me was that LaFevre promised to pay $5000 for the blueprints and then went into business on them but never paid. Thus, on this version, he does not even own the physical blueprints. Note the "possibly" in the paragraph above. I know about copyright law; it is part of what I do. Suppose I were to throw the original manuscript of a published book in the bin and you came along and picked it out. You would own nothing. The copyright would remain with me; I could publish the book again. Whether you would own the right even to photograph the physical manuscript would be a tricky question. (I called a fellow at the university where they want to keep my archive and he says this case is specifically permitted in the contract I will sign with them, because the only legal judgements remotely relevant relate to the physical and reproductive ownership of *letters* written to someone that biographers want to quote. In other words, nobody actually knows for sure.) Thus LaFevre, regardless of whether he paid the fellow who picked the plans out of the dumpster, might not own even the right to stop anyone else reprinting the particular blueprints he holds. Furthermore, if any particular plan or set of details or specifications from the materials LaFevre claims to own was ever published in professional or hobby publications, as was common those days, there is a great likelihood that the copyright has either passed into the public domain or that a case will stand for fair dealing with the material right up to the limit of what was published before. (Fair dealing is the concept in copyright law of how much you may quote out of a single creative unit without permission or payment e.g. for criticism or instruction, very little out of a short poem, a bit more out of a long novel.) Of course, just because someone digs a bunch of discarded blueprints out of the dumpster does not mean he owns the name of the defunct corporation that once operated out of the building behind the dumpster. I therefore suspect that if, as Cal suggests, Patrick wants to wind a Peerless TFA-204 replacement output transformer for a WE91, call it a Peerless, and offer it for public sale, the nut in Philly will have no legal right to stop him. I suspect that the same applies to all the other once great names the nut in Philly claims to own. Since whoever may in fact own those names now have in almost twenty years done nothing about Michael LaFevre sullying their names, I don't imagine they will act against Patrick either. Beware though, the position may be very different with Mac, Marantz or Linear Standards, as the MacIntosh and Marantz names belong to currently active producers, (I don't know about Linear Standards but the safest thing is always to assume someone else owns the rights.) I imagine the present owners of those corporations took over all the intellectual and other property rights of the original owners. Those guys may bite back if their property is stolen for profit and, in theory at least, they may even bite some hobbyist making a single pair of their trannies for his own use. The common exemption for hobbyists is a favour from the owners, not a matter of law, and where the exemption for hobbyists is not in fact given but taken by hobbyists the reason they get away with it is that it is too much bother for a large corporation to have them prosecuted for the theft. ***** So, Patrick can very likely freely use several ancient names without fear of retribution, and wind their designs without royalty. Thus the question becomes: Why should he want to? Some of those ancient transformers were great. I had some wound to an US Army spec for 845 in broadcast stations and you can't buy anything that good today off the shelf and the price for custom work would be prohibitive. Also some superb audio chokes I got in the same batch which had stood in a store for fifty years since the end of the Berlin Airlift. But, in fact, these were semi-custom jobs for a price-no-object customer. Your average vintage tranny was, by today's standards, trash. That is why Cal is so careful to specify top dollar makes rather than speaking generally of vintage trannies. The reason your Sol Marantz, your Theo Williamson, your Peter Walker, your Harold Leak, none of them mindless big spenders, all of them canny businessmen, went the expensive way of specifying their own trannies for custom manufacture under strict quality controls, was that what they could buy off the shelf was inadequate. It is these lowest common denominator transformers, built down to a price, that are in the blueprints LaFevre claims to own. He published a huge catalogue of transformers that in theory he would wind to order. I looked into it and they were very commonplace transformers when they were designed, for which LaFevre would prices for which I could get custom winds more suitable to modern amps. (LaFevre's best tranny and also his best value for money was the Dynaco replacement Ned Carlson used to sell, and even that was expensive.) It should be noted that when LaFevre tried to move upmarket with better transformers under his own house brand, Magnequest, he had altogether new transformers designed by journeyman designers (you can ignore his claims that he designed them himself - - he admitted those were ten years of lies). In other words, Creepy Mike knew that the transformers in the blueprints, whatever the ownership of the proprietary rights to the designs, were inferior. As noted before, I had a pair of what is widely considered the best of the antique designs LaFevre claims to own, the Peerless TFA-204, which is billed as a transformer originally recommended by WE as a replacement item for the output on the WECO Model 91, presumably originally built to the same spec by Peerless. Let's leave aside the fact that my set was so incompetently constructed by LaFevre that one fell apart in the post, leave aside that the frame was lightweight enough to bend in the post (photo in my review of the SEX amp in Glass Audio Vol 9 No 6 1997). Let us for the moment assume the rest of the thing was competently wound and otherwise built with materials to the WE specification. On the assumption that the Magnequest Peerless TFA204 was at least internally competently built to WE spec, I tested it against the standard TV vertical transformer from Thordarson on the SEX kit amp, for which the TFA204 was offered as an upgrade that *doubled* the price of the amp. The Magnequest Peerless TFA-204 could not gain a conclusive victory over the standard ten buck surplus TV transformers. (Description in my review of the SEX amp in Glass Audio Vol 9 No 6 1997.) The Magnequest Peerless TFA-204 copy of the "WECO" transformer had a measured primary inductance of 6H. I stand to be corrected, but I seem to remember that the original WECO Model 91 spec was for 9H. I conclude that if Patrick wants to wind ancient designs rather than his own modern designs, he'd do better to find something a lot upmarket from the Peerless TFA-204. I have no doubt that Patrick could wind and otherwise manufacture Peerless TFA-204 more true to the specification of the original than LaFevre's Magnequest spaghetti pullery, and do an allround more competent job in the construction, but the question remains: why should he want to make something so compromised by today's expectations? **** I don't know anything about the Mac and Marantz and Linear Technology transformers Cal chooses as worthy of reproduction. My experience with a modern reproduction of a famous Peerless (albeit by a suspect winder) is unhappy; I am not at all certain that, considering the miniscule size of this Peerless TFA204, the experience would be all that much happier with an exact copy of the vintage tranny by a competent winder. But I'm left wondering whether, if I built, say, a CFB amp today, let's say not just inspired by the Quad II but an actual copy, would I use original Quad transformers from my junkbox (or exact new-wind copies) - - or would I upspec by choosing something from Menno van der Veen's Specialist line at Plitron or even a new custom design? Andre Jute |
|
#2
|
|||
|
|||
|
I feel I should make a few things clear. First, I am not a magnetics
designer, nor am I an attorney. Before you spend a lot of money, you should spend a little talking to the above, if you are gearing up to do a business venture. However, intellectual property essentially consists of three broad groups of things: copyrights,trademarks,and service marks; patents; and trade secrets. Trade Secrets consists of information imparted by an individual or corporation in the course of employment or contract fulfillment. If you didn't work for Mike, or, _if_ he validly held the corporate assets, the former Peerless/Acrosound/etc, you simply are not subject to trade secret infringement action. Dismantling an old one, ordering copies of prints in the National Archives, or finding other design information which has become available, is not covered under trade secret law. Copyright applies to written, photographed, or otherwise recorded information in its published form. The facts themselves are not subject to copyright. Sam Shaw's photograpy of Marilyn on the subway grate is covered by copyright but if a onlooker had photographed her at that same time and place and arrived with virtually the same photo, Shaw's estate would have no claim to that photo. You can't copyright a transformer. You can copyright a drawing or wind sheet but if I draw one from that that conveys the exact same information, I may copyright it also-actually, I may register and enforce the copyright, or I may put it in the public domain, and you have no more control over my work than I do of yours. The Peerless and other logos and trademarks may validly belong to Mr. LeFevre, but that only means that _if he does_ you can't use them. You can't call your transformer a Peerless, but you sure can say "Replaces Peerless 20-20 Series xxxx". I can't make diesel engine pistons and call them "Caterpillar" or put the Cat logo on them, but I very certainly can say "Replaces XXX piston for 3406 engines XXX-YYY". Cat can't outlaw my pistons (unless they embody a patented feature Cat owns the patent to). All they can do is advertise that my "willfit" pistons aren't as good-in their opinion. Patents are for 17 years and you _can_ get one extension for another 17 years. All the transformers we are discussing are much more than 34 years old. To put a fine and absolutely ironclad point to it, Mike LeFevre DOES NOT have any exclusive legal right to make a transformer identical to any old one of any make whatsoever. Whether you concede him to have a moral right to do so is another matter, but only someone living in a fantasyland could conceivably concede him that. The biggest problem is really that there are not all that many people wanting to buy them and being willing to spend the necessary money to do so. But taking a Peerless or any other transformer much over 34 years old to any winder in the world and having him do them, if he can-except for the name and logo stamped thereon-is 100% proper, right, and lawful. And if neither yoo or the winder worked for the company in question and there is no valid PATENT involved that's true of Manley/VTL, ARC, DeParavicini, or anyone else making new ones as well. They may not like it, just as Caterpillar doesn't like offbrand parts in "their" engines and Sam Shaw was ****ed when a gawker's Rollei produced (with many years' delay...) a MM poster in the late sixties. Do you live your life to be liked by Mikey or other weird audio people? |
|
#3
|
|||
|
|||
|
|
|
#4
|
|||
|
|||
|
Thus his concept of what is proprietory information is extraordinarily wide. If the designs of the transformers in question were patented by "utility" patents (the kind of patent people normally think of when they hear something is patented), the patents would have expired by now. Patents last about 17 years (last I heard, who knows they may have changed it for new patents) and after that it's public domain. As far as the names of the transformers is concerned, it's similar to brewing up beer that tastes like Budwieser and then selling it as Budweiser. That's not legal, but you could call it your own name and say "tastes similar to Bud" (I'm ignoring the issue if Bud tastes good or not...). |
|
#5
|
|||
|
|||
|
Stewart Pinkerton wrote: (snip) To put a fine and absolutely ironclad point to it, Mike LeFevre DOES NOT have any exclusive legal right to make a transformer identical to any old one of any make whatsoever. Whether you concede him to have a moral right to do so is another matter, but only someone living in a fantasyland could conceivably concede him that. Actually, more to the point, why would anyone be dumb enough to *want* a 40 year-old tranny design, when far superior units can be wound from modern materials, with turns ratios matched to modern requirements? Part of the market is ostensibly for replacements, but a lot of people specifically want to re-create a famed design as well. And no, wideband LF magnetics has NOT made huge strides in recent years-in the solid state era the magnetics were largely done away with, as you know, so it became a little bit of a 'black art'. Not as much as people like LeFevre would have one believe, because wind houses have been doing military stuff with similar problems all along, for one thing, and because there still are a lot of the old guys (actually, most _winders_ were female) still at it. The tubes, for those using them, and the speaker impedances are the same, so the turns ratios are the same also. One could certainly buy better output transformers new in 1962 from electronics houses than one can today. Modern insulations and pottants are better and to a lesser extent so are the core materials, but no one, ironically including LeFevre, is winding better OPTs as shelf stock for open sale today. There are some nice transformers available now, but in no where near the variety as then. |
|
#6
|
|||
|
|||
|
Stewart Pinkerton wrote:
Actually, more to the point, why would anyone be dumb enough to *want* a 40 year-old tranny design, when far superior units can be wound from modern materials, with turns ratios matched to modern requirements? Makes me laugh when people on ebay spend thousands on WE telephone repeater amps to listen to music with. Never occured to them that the amps were designed with speech and have a limited frequency response. Adam |
|
#7
|
|||
|
|||
|
|
|
#8
|
|||
|
|||
|
The WE audio amps on eBay are not telephone repeater amps, they are WE
_theater_ amps. Had nothing to do with the telephone, which is why the business was spun off to form Altec. |
|
#9
|
|||
|
|||
|
Depends on who the who is. But the "masses" even in the high end
don't care, because they are ignorant, and many of the people in tube DIY are either really cheap or willfully stupid. But there is still a small core group of people, with the knowledge, the skills, the test equipment, the motivation, to do good work. The rest can **** off and die. All progress is made by that small elite. |
|
#11
|
|||
|
|||
|
|
|
#12
|
|||
|
|||
|
|
|
#13
|
|||
|
|||
|
" wrote: wrote: Turner .... likes to wind his own, which is fine, although I do wish he'd wind the good American kind like Mac, Marantz or Linear Standards, or even Peerless to **** the nut in Philly off. It is an interesting question who now owns the rights to the original design specifications to the likes of Mac, Marantz or Linear Standards, or even Peerless and thus who can reproduce them. When the nut in Philly as you call him was constantly on my ass with his gang, about thirty separate parties wrote to me about the ownership of the great old transformer brand names, including Peerless, that Michael LaFevre of Magnequest claims to own. One of these letters was from the man from whom LaCreepy bought the Magnequest business. The others all offered roughly the same story, some with additional detail. Mike LaFevre claims to own great names like Peerless, and the rights to all their designs. He ferociously attacks anyone who question his claim to own the rights and refuses to publish even specifications that were commonly published when the designs he claims to own were originally made. He has publicly threatened legal action against anyone who reverse engineers e.g. a Peerless transformer whether supplied by him or not. He has publicly refused to supply what his henchmen describe as "troublemakers" for the stated reason that they would test (!) or copy these ancient transformers. He has threatened legal action against anyone publishing newly taken test results of one of his transformers. Thus his concept of what is proprietory information is extraordinarily wide. (This should be interpreted in the light of the known fact that LaFevre's legal knowledge is extraordinarily lacking for someone whose training and experience is in political management, not engineering. For instance, when he tried to sue me, his lawyer told him to grow up.) However, those who contest the Magnequest claim to own the names and all proprietary rights to all the original designs say that all that happened was that person A took a bunch of blueprints out of a dumpster and sold them to person B, person B being Michael LaFevre of what is now Magnequest Transformers, Philadelphia. If that is true all that passed was possibly the rights to reprint the blueprints in LaFevre's hand and even here there is a complication. The story repeatedly told to me was that LaFevre promised to pay $5000 for the blueprints and then went into business on them but never paid. Thus, on this version, he does not even own the physical blueprints. Note the "possibly" in the paragraph above. I know about copyright law; it is part of what I do. Suppose I were to throw the original manuscript of a published book in the bin and you came along and picked it out. You would own nothing. The copyright would remain with me; I could publish the book again. Whether you would own the right even to photograph the physical manuscript would be a tricky question. (I called a fellow at the university where they want to keep my archive and he says this case is specifically permitted in the contract I will sign with them, because the only legal judgements remotely relevant relate to the physical and reproductive ownership of *letters* written to someone that biographers want to quote. In other words, nobody actually knows for sure.) Thus LaFevre, regardless of whether he paid the fellow who picked the plans out of the dumpster, might not own even the right to stop anyone else reprinting the particular blueprints he holds. Furthermore, if any particular plan or set of details or specifications from the materials LaFevre claims to own was ever published in professional or hobby publications, as was common those days, there is a great likelihood that the copyright has either passed into the public domain or that a case will stand for fair dealing with the material right up to the limit of what was published before. (Fair dealing is the concept in copyright law of how much you may quote out of a single creative unit without permission or payment e.g. for criticism or instruction, very little out of a short poem, a bit more out of a long novel.) Of course, just because someone digs a bunch of discarded blueprints out of the dumpster does not mean he owns the name of the defunct corporation that once operated out of the building behind the dumpster. I therefore suspect that if, as Cal suggests, Patrick wants to wind a Peerless TFA-204 replacement output transformer for a WE91, call it a Peerless, and offer it for public sale, the nut in Philly will have no legal right to stop him. I suspect that the same applies to all the other once great names the nut in Philly claims to own. Since whoever may in fact own those names now have in almost twenty years done nothing about Michael LaFevre sullying their names, I don't imagine they will act against Patrick either. Even if I set out to wind replacement OPTs for McIntosh, Peerless, Marantz, Quad, Leak, et all, I'd never call them by the original makers part number. They'd be Turner OPT no3, or whatever number, designed independantly and without reverse engineering. They may resemble the original brand name and be a substitute, but be an improvement if I could factor that in. Why go to the trouble of reproducing 1940 to 1960 mediocrity????. Any case brought against me by LeFevre, or anyone else would be viewed as a frivolous complaint, and thrown out of court. Beware though, the position may be very different with Mac, Marantz or Linear Standards, as the MacIntosh and Marantz names belong to currently active producers, (I don't know about Linear Standards but the safest thing is always to assume someone else owns the rights.) I imagine the present owners of those corporations took over all the intellectual and other property rights of the original owners. Those guys may bite back if their property is stolen for profit and, in theory at least, they may even bite some hobbyist making a single pair of their trannies for his own use. The common exemption for hobbyists is a favour from the owners, not a matter of law, and where the exemption for hobbyists is not in fact given but taken by hobbyists the reason they get away with it is that it is too much bother for a large corporation to have them prosecuted for the theft. ***** So, Patrick can very likely freely use several ancient names without fear of retribution, and wind their designs without royalty. Thus the question becomes: Why should he want to? I would only offer what I thought was a an upgrade. See above. The McIntosh OPT has special extra insulated wires and bifilar windings. Its a difficult beast to wind. Anyone successfully copying a McI OPT deserves a damn medal. But the EAR509 amp by Tim DeParavicini has almost exactly the same type of output stage, unity coupled, but an OPT with separated windings but no bilfilars, and he uses capacitors to shunt the leakage inductance across common signal potential ends of windings. This is a better way to wind a McI type of tranny because there is far less likelyhood of a short between the B+ of 450v across the anode and cathode bifilar windings with hundreds of turns all packed in close and touching each other. I'd only have to make my OPTs differ a little but work just the same and not a soul could accuse me of stealing intellectual property. Some of those ancient transformers were great. I had some wound to an US Army spec for 845 in broadcast stations and you can't buy anything that good today off the shelf and the price for custom work would be prohibitive. Yeah, broadcast gear is sometimes very good. But that's the tiny minority of the tonnage of OPTs made; most were for PA or non discriminating domestic amplifiers. Some military transfromers were terrific. I bought some surplus potted trannies meant for the Navy and they are very nice items. Also some superb audio chokes I got in the same batch which had stood in a store for fifty years since the end of the Berlin Airlift. But, in fact, these were semi-custom jobs for a price-no-object customer. Your average vintage tranny was, by today's standards, trash. That is why Cal is so careful to specify top dollar makes rather than speaking generally of vintage trannies. The reason your Sol Marantz, your Theo Williamson, your Peter Walker, your Harold Leak, none of them mindless big spenders, all of them canny businessmen, went the expensive way of specifying their own trannies for custom manufacture under strict quality controls, was that what they could buy off the shelf was inadequate. I am not so sure. In Oz, A&R of Melbourne and Fergesson of Sydney wound a range of OPTs for end users, some hi-fi, potted, very nice, even interleaved 4P x 3S. Wow. The majority purchased were low fi, non potted, with horrid cores, high losses, and for a typical 25 watt PP OPT leakage was 50 mH referred to the primary. Now I have rewired two lots of Leak Point One amps for two clients. One pair had shorted turns in one OPT, so the owner got me to purchase a pair of "wound to original spec" trannies from a Sydney winder I won't name in 1995. They were meant for any UL PP amp with EL34, KT66. They were indeed about as horrible as the original Leak crap of 1950+. I tested the good channel and discovered LL = 50mH + and high winding losses, but at least they had a good bass extension. I stripped the OPT down with the shorted turns. It used a non wasteless core with larger window size than wasteless to fit the 3,800 P turns on and keep the core size low, hence chassis size and weight. The P wire was nearly as thin as a hair. There were 3 P sections and two S sections, so hence the high LL. Almost any old crap could give better HF response and lower winding losses along with better natural resistance to overheating of windings when an output tube became saturated with 400mA for a few minutes before it dies, when sometimes it also takes out the OPT winding, or shorts a couple of turns. I don't much like Quad II trannies, rather too small for 20 watts, rather high Fsat, but just sufficient for the purpose. They were designed with almost no ability to be pushed any harder so virtually no ugrade ability, allowing KT88, and 40 watts of class A. Leak and Quad et all wound their own to make more money, not because they couldn't find something suitable and cheap. In house manufacture gives the profit that a subcontractor might make, and it gives you control over the product, as you said. There were plenty of skilled tranny winders ready to work winding thousands to trannies for reputable companies like Quad and Leak. The transformers are the major part of tube amp making, so in house is sensible. Making one's own tubes or transistors isn't sensible, since the scales of operation have to be huge to get the profit. The best from the Oz makers were indeed very nice, and I'd suggest the best from the British makers also was very good, and simply too expensive for most amp makers to use, when cheaper more "critically designed" OPTs could be done in-house. Then the small volume "out" house makers may have had trouble filling orders; No such problems with in-house workers. But nowdays the production runs are far smaller for tube amps and employing anyone on wages is fraught with liabilities, so many companies source their wound items from out-house subcontractors. These subbies my have a very good name, like Tango, Tamura, Pliton, Lundahl, etc, and so it would add value to use such outhouse makers. ( pardon the expression, "outhouse makers"; they are often a very skilled and respectable bunch of dudes without whom the world would be worse off :-] .) It is these lowest common denominator transformers, built down to a price, that are in the blueprints LaFevre claims to own. He published a huge catalogue of transformers that in theory he would wind to order. I looked into it and they were very commonplace transformers when they were designed, for which LaFevre would prices for which I could get custom winds more suitable to modern amps. (LaFevre's best tranny and also his best value for money was the Dynaco replacement Ned Carlson used to sell, and even that was expensive.) Just exactly what LeFevre has or doesn't have in his stack of blueprints is conjecture. Are his wares expensive? I don't have a clue, gees, there are big price differences around, and some conflicting claims made about the sound and so who does one believe? What on earth is the best value? Its hard to know. I am not exactly obsessive about what Mr LeF does or doesn't do. It should be noted that when LaFevre tried to move upmarket with better transformers under his own house brand, Magnequest, he had altogether new transformers designed by journeyman designers (you can ignore his claims that he designed them himself - - he admitted those were ten years of lies). In other words, Creepy Mike knew that the transformers in the blueprints, whatever the ownership of the proprietary rights to the designs, were inferior. As noted before, I had a pair of what is widely considered the best of the antique designs LaFevre claims to own, the Peerless TFA-204, which is billed as a transformer originally recommended by WE as a replacement item for the output on the WECO Model 91, presumably originally built to the same spec by Peerless. Let's leave aside the fact that my set was so incompetently constructed by LaFevre that one fell apart in the post, leave aside that the frame was lightweight enough to bend in the post (photo in my review of the SEX amp in Glass Audio Vol 9 No 6 1997). Let us for the moment assume the rest of the thing was competently wound and otherwise built with materials to the WE specification. On the assumption that the Magnequest Peerless TFA204 was at least internally competently built to WE spec, I tested it against the standard TV vertical transformer from Thordarson on the SEX kit amp, for which the TFA204 was offered as an upgrade that *doubled* the price of the amp. The Magnequest Peerless TFA-204 could not gain a conclusive victory over the standard ten buck surplus TV transformers. (Description in my review of the SEX amp in Glass Audio Vol 9 No 6 1997.) The Magnequest Peerless TFA-204 copy of the "WECO" transformer had a measured primary inductance of 6H. I stand to be corrected, but I seem to remember that the original WECO Model 91 spec was for 9H. To sum all that up, buyer beware! The more one learns about OPTs, the less one is inclined to buy anything, and the more one is likely to save another week's wages to pay for something really good. The really good maker gurantees his specs, all of which are available. No speccy, me no buyee, unless 20 ppl I know say the product is excellent because that's what they have tried. I conclude that if Patrick wants to wind ancient designs rather than his own modern designs, he'd do better to find something a lot upmarket from the Peerless TFA-204. I have no doubt that Patrick could wind and otherwise manufacture Peerless TFA-204 more true to the specification of the original than LaFevre's Magnequest spaghetti pullery, and do an allround more competent job in the construction, but the question remains: why should he want to make something so compromised by today's expectations? I am only interested in making something that gives wide bandwidth at full power and with winding losses under 5%. I use lots of iron for the watts, and fill the widows right up with turns. I believe the GOSS cores are the best I can buy. But I don't like winding a few trannies for ppl wanting to upgrade their ST70 or build a new amp; They invariably have trouble accepting that I can't and won't do it as cheaply as Hammond does it. Its just such a fickle market, so I prefer to offer a whole amp than just wind OPTs. **** I don't know anything about the Mac and Marantz and Linear Technology transformers Cal chooses as worthy of reproduction. My experience with a modern reproduction of a famous Peerless (albeit by a suspect winder) is unhappy; I am not at all certain that, considering the miniscule size of this Peerless TFA204, the experience would be all that much happier with an exact copy of the vintage tranny by a competent winder. But I'm left wondering whether, if I built, say, a CFB amp today, let's say not just inspired by the Quad II but an actual copy, would I use original Quad transformers from my junkbox (or exact new-wind copies) - - or would I upspec by choosing something from Menno van der Veen's Specialist line at Plitron or even a new custom design? I don't really *need* to join the ranks of the winders offering designs suitable for whatever project you have in mind. Some do a sterling job, and I'd be battling all the way to get to their quality for the price. Sowter winds things to order, and has a good reputation. One has to wait months with some suppliers to get what one wants. They are busy with a stream of orders. One dude I know bought SET trannies from Sowter which were about 4 Kgs for his EL84 amps. Then he changed to Vaic 32B 300B which gave him around 9 triode watts instead of 4 pentode watts, man, what a difference, and last time I heard his sytem using Tannoy concentrics in sand large sand filled enclosures, the sound was just glorious. Always use something technically too good for what one wants; ie, if you want a 300B OPT and can find an OPT with 20H at 100mA for 5k, then grab it, its going to deliver better than a critically designed tranny. The extra $100 is only the cost of a spare tube, or a spare car tyre, a few meals at a restaurant. The taste of cheapness remains sour for years aftewards. There is a guidline in RDH4 where they spell out the recommended weight of an OPT for a given number of watts, a pounds/watts ratio. Very few makers paid much attention to RDH4. I don't exactly know what Le F did, and I don't much care. We could move along to simply discuss what should be OK for 300B, or any other config without biting at the heels of all these other makers for too long lest we stir them unnecessarily. The world and its technocrats and marketeers are never to be perfect. Let them stay asleep, so to we may get a night's peaceful rest. Patrick Turner. Andre Jute |
|
#14
|
|||
|
|||
|
Simply put the best of the classic designs are probably the best that have ever been made to date. Can they be improved on? Maybe, but probably only a little, because the laws of physics haven't changed, copper hasn't changed, and core materials have changed very little. There are people who take pride in refusing to work off past ideas and working it out themselves from first principles. IMO life is too short for that. |
|
#15
|
|||
|
|||
|
There are people who take pride in refusing to work off past ideas and working it out themselves from first principles. IMO life is too short for that. Usually true, but with some projects someone doing that may come up with a good new idea. Avoiding the trap of "This is how it's done". Long odds though.... |
|
#16
|
|||
|
|||
|
|
| Reply |
| Thread Tools | |
| Display Modes | |
|
|
Similar Threads
|
||||
| Thread | Forum | |||
| KISS 117 by Andre Jute | Vacuum Tubes | |||
| Interested in high-performance tube-based AM tuner designs | Vacuum Tubes | |||
| Building a circuit with no power transformer ? | Pro Audio | |||
| Question about Low DCR power transformer for filament supply | Vacuum Tubes | |||
| Reversing a Power Transformer | Vacuum Tubes | |||
Linear Mode
