Help a first timer to select...

[Eli Duttman]

C-J,

That you have some budget flexibility is a good thing. "El Cheapo" can serve as food for thought. Better O/P "iron" allows you to do MORE. However, the 12AT7/ECC81 differential phase splitter will serve you WELL in a more powerful circuit. Push/pull O/P topology cancels internally generated even order harmonic distortion. When a PP distortion spectrum of odd harmonics is combined with the spectrum of the 'T7, the result is a PLEASING 2nd>3rd>4th ... 2 stage monoblocks of 'T7 splitter drivers and EL34 "finals" need to be combined with a line stage that has a little gain. That fits well with your stated objective.

[Majestic]

Originally posted by Eli Duttman
C-J,

That you have some budget flexibility is a good thing. "El Cheapo" can serve as food for thought. Better O/P "iron" allows you to do MORE. However, the 12AT7/ECC81 differential phase splitter will serve you WELL in a more powerful circuit. Push/pull O/P topology cancels internally generated even order harmonic distortion. When a PP distortion spectrum of odd harmonics is combined with the spectrum of the 'T7, the result is a PLEASING 2nd>3rd>4th ... 2 stage monoblocks of 'T7 splitter drivers and EL34 "finals" need to be combined with a line stage that has a little gain. That fits well with your stated objective.

Hmm, that sounds interesting. My own pair of PP's (Mullard 5-20 circuit as it turns out) use a 12AX7 in that position. Was one day going to try the 12BZ7 in there. But now I'll have to give the 12AT7 a go too!

Is that the best sounding driver tube you've tried in your own PP amps? What else have you sampled??

Always pleased to hear the results of others' experiments!

[rickl]

If I was going to build an amp and had to source everything, I'd look at El Cheapo too. See Eli's link above.

Eli's design seems to make a lot of sense, fairly simple but still should sound great. What I really like is most of the parts can be sourced from Jim "Mr. Citation" McShane. My guess Jim isn't making a dime on this but just wants to help us DIY tube guys.

Remaining parts can be sourced from vendors listed on the thread.

I'm currently working on a couple 6v6 amps and have another Dynaco Mark III in queue otherwise I'd build this one.

rick