I'm not normally a fan of solder- slingers, but...

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In Reply to: Is it a VT-52 amp,No its a 45 amp, No its a 50, No its a 811-3A posted by drummerwill on March 15, 2000 at 12:06:16:

Sorry, that was an inside joke.
Actually, I'm looking forward to doing some mods my self later this year, and your approach is one I had been wondering about. It seems to me that even with 2A3 and 300B's as in the Cary/AES SE1, you cannot really optimize for more than one tube in an amp without some compensating circuitry.
Gordon Rankin's approach with the Atlas is to have an auto-sensing circuit in which "The power supply...automaticically adjusts BIAS and Filament Voltage to optimize the circuit for the most power," but it is still limited to 300B's and variants. His new Gemini monoblocks will have switches to change from 45's to 2A3's, which sounds like a great amp idea.
However, your DIY approach seems to be the best for those with limited funds. What variables affect output tranny performance besides output impedance? (Next thing you know, you'll be modifying OPT's to be pluggable so you can switch them too!)
Although guys like my buddy Jack G. like to buy and sell amps to roll tubes in, they have apparently never appreciated the odor of solder resin, and never cared about DIY . I'd be very interested in a multitube design, and will follow your project with great interest. It sounds like selecting tubes with the same output impedance is the critical parameter if your power supply can supply the highest voltages necessary.
But doesn't that 50w dropping resistor get hot? It must be pretty big too.
Dave van Harn

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Follow Ups Full Thread

Topic - Is it a VT-52 amp,No its a 45 amp, No its a 50, No its a 811-3A - drummerwill 12:06:16 03/15/00 (4)

I'm not normally a fan of solder- slingers, but... - Dave VH 03/15/0015:46:40 03/15/00 (1)

Re: I'm not normally a fan of solder- slingers, but... - drummerwill 19:29:42 03/15/00 (0)

Cool :-) - Jack G 12:29:30 03/15/00 (1)

Re: Cool :-) - drummerwill 19:40:11 03/15/00 (0)

Follow Ups

I'm not normally a fan of solder- slingers, but... - Dave VH 03/15/0015:46:40 03/15/00 (1)

Re: I'm not normally a fan of solder- slingers, but... - drummerwill 19:29:42 03/15/00 (0)

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