I could be mistaken, but I believe this gentleman has been trying to build a tube amplifier that works in an SE configuration with a driver and he has come up with this:
a3univ.htm
I suspect that such a 'universal' design is going to involve big trade-offs, but I still think it is really interesting!
FYI, it is in Japanese, but I get an automatic translation using Chrome as my web browser. This may work for those who don't have that capability.
https://translate.google.com/#en/ru/http%3A%2F%2Fwww2u.biglobe.ne.jp%2F~hu_amp%2Fa3univ.htm
a3univ.htm
I suspect that such a 'universal' design is going to involve big trade-offs, but I still think it is really interesting!
FYI, it is in Japanese, but I get an automatic translation using Chrome as my web browser. This may work for those who don't have that capability.
https://translate.google.com/#en/ru/http%3A%2F%2Fwww2u.biglobe.ne.jp%2F~hu_amp%2Fa3univ.htm
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I can't quite see the point. It would be like designing a car to run on any fuel and take any size tyres. Interesting student exercise but nothing to do with real life.
Might be fireworks as well.
12AU7 triode in parallel with a 6CA7 just does not seem like sound engineering practice.
12AU7 triode in parallel with a 6CA7 just does not seem like sound engineering practice.
You missed the "OR".
Agreed that of questionable value for hifi.
Good for MI though. I think the amp that are plug n play for EL34/6L6GC/KT88 are the cat's meow
Does everything have to have something to do with real life?
Perhaps it is nothing more than an interesting student exercise as you say. Why is that a bad thing? I thought it was interesting. I didn't say it was the perfect amplifier and everyone should build one.
Actually I did see the "OR" and was thinking "Logical OR" with both signals present.
The schematic is not complete since it is drawn in such a manner that there is a conflict in using dual Triodes. It is not possible to insert a 12AU7 and 6CA7 without violating the "OR". Additional sockets are necessary to be able to use a 12AU7 for the input Triode and NOT populate the output Triode position.
If you leave out both triodes, there is no plate load on the input pentode, and the circuit won't work.
The schematic is not complete since it is drawn in such a manner that there is a conflict in using dual Triodes. It is not possible to insert a 12AU7 and 6CA7 without violating the "OR". Additional sockets are necessary to be able to use a 12AU7 for the input Triode and NOT populate the output Triode position.
If you leave out both triodes, there is no plate load on the input pentode, and the circuit won't work.
OK, let me rephrase. What's wrong with pointless? Frankly, I have a bunch of Luxman products that sound great. Why spend time building tube amps?
I think people have hobbies because they like them. I know I do. They don't have to have a point.
I think I said it was pointless, not "wrong".
A car which can run on any fuel and take any size tyres might still get you from A to B, but it probably would not be considered a sensible means of transport. Similarly, an amp which can take any valve might allow you to listen to music but it might not be considered a useful domestic item.
Why do you insist on importing moral attributes which I did not mention?
A car which can run on any fuel and take any size tyres might still get you from A to B, but it probably would not be considered a sensible means of transport. Similarly, an amp which can take any valve might allow you to listen to music but it might not be considered a useful domestic item.
Why do you insist on importing moral attributes which I did not mention?
In the Crawford Auto Museum at the Western Reserve Historical Society there's a 60's era Chrysler with a turbine engine which will run on anything from orange juice, castor oil, kerosene or gasoline.
I think perhaps the word 'pointless' means different things to you and me, and if that is the case, I certainly apologize. When someone tells me something is pointless, I think they mean they don't like it and no one should do it.
That is what 'pointless' means to me. If it has a different meaning to you, mea culpa.
OK. 'Pointless' to me means I would not do it, and I can't see why anyone else would want to do it - but they are, of course, free to do it if they want to. A worthless exercise, which is not the same thing as a harmful exercise. Daft, but not wrong.
The schematic comes from, I think a Japanese website, that's into STC amps (there should be a STC discussion going on somewhere in here).
Among many designs that are uniquely aimed for ONE and only ONE kind of power tube are some universal designs, that, I believe, are made in order to fit odd tubes that weren't on the "list of designs for standard tubes".
I'm not sure this design was aimed for a multitube amp where we could listen to the tube of today. Propably it's more of an experimental setup, testing the STC design will all kinds of tubes - a breadbord, simply.
I would advice WW Jones to look up the other "fixed" designs and use the one that goes with the tubes you had in mind, remembering that this is an odd topology and, as you will learn if you go this way, too many people have too many opinions.
Finally I'd like to add that I have built two smaller amps, based on ECL82, using this specific topolgy and both worked fine and did actually send some nice amplified music signals to my speakers.
Among many designs that are uniquely aimed for ONE and only ONE kind of power tube are some universal designs, that, I believe, are made in order to fit odd tubes that weren't on the "list of designs for standard tubes".
I'm not sure this design was aimed for a multitube amp where we could listen to the tube of today. Propably it's more of an experimental setup, testing the STC design will all kinds of tubes - a breadbord, simply.
I would advice WW Jones to look up the other "fixed" designs and use the one that goes with the tubes you had in mind, remembering that this is an odd topology and, as you will learn if you go this way, too many people have too many opinions.
Finally I'd like to add that I have built two smaller amps, based on ECL82, using this specific topolgy and both worked fine and did actually send some nice amplified music signals to my speakers.
Thanks! I don't generally have a particular amp or tube in mind. I like oddball things. I like things no one else is doing at the moment. I build lots of stuff, from standard 6AQ5 to 117P7GT and 26A7GT. I get lots of "that's stupid, why would you do that?" comments, but I just like weird stuff. Perhaps just for the sake of seeing if it could be done. That's why I found this so interesting.
I agree, it looks like a test harness of some kind. I like test harnesses.
Guess you were to that page describing a row of STC amps. I cannot remember the address, sitting in thundering fr*gging Chicago with my iPad trying to survive yet another week, but there should have been dedicated designs.
So if you are into odd kind of vacuum filled glassbulbs, go ahead with that "breadboard" type of thing.
BTW, for those who just have seen the design proposed, here are the rest:
http://www2u.biglobe.ne.jp/~hu_amp/amput3e.htm
So if you are into odd kind of vacuum filled glassbulbs, go ahead with that "breadboard" type of thing.
BTW, for those who just have seen the design proposed, here are the rest:
http://www2u.biglobe.ne.jp/~hu_amp/amput3e.htm
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