WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
Building, troubleshooting and testing of these amplifiers should only be
performed by someone who is thoroughly familiar with
the safety precautions around high voltages.
Look again. EL34 is triode strapped. Power supply is tube (5U4). No 6SN7. if You are able to do that can try to design your own driver stage or whole amply otherwise You've to accept what community has.
The whole schematic are somewhere over internet, search Michel Leluaux EL3. I have the full article if You are really going to built it.
Hey, Thinking about building this. Has anyone here tried (or heard it). I'm thinking maybe some custom wound OPT's. I don't quite understand the high B+ and high OPT input resistance. Could someone explain it in simple terms, as I am just learning to read plate curves. Also any overall opinions on the design would be welcome. Thanks Jay
Hmmm, That one electron design is interesting. I allready have a PT, (salvaged) but it doesn't look like it has enough heater current. In its original application it was running 4.56 amps worth of heaters. The one electron design would call for 8 amps. Tom's circuit calls for 4.2. I might add this is my first DIY amp, so I'm trying to use stuff I have laying around here in the man cave. Also Tom's circuit looks a little simpler for a first timer, I just don't understand the high 10K load he has the tube working into, or the seemingly high B+. I've had some help doing load lines, but am having trouble deciphering exactly what they are telling me. I guess I could just build it, but I would kind of like to understand the effects of the 10K Z. Thinking of doing the power supply like this.