Mini amp using 12AU7's as power tubes?

[porkchop61]

I want to build a stereo "mini amp" using a 12AU7's as the power tubes. I'd like this to be an OTL design (just to save space), but PP is okay. I was thinking of using a 12AX7 as the preamp tube, and a 12AT7 as the driver for the 12AU7. Has anyone ever seen a design for this type of amp? Maybe I just have to start breadboarding the circuit to see how things sound. It doesn't have to be high power, <=1W is okay.

Any tips for a design would be greatly appreciated as I've never designed an amp before.

Thanks
Glenn

[poynton]

Hi,

I had thoughts along this line some time ago.
I've not done anything about it though!!

Here's the link :-

EAR Yoshino V20 Amplifier


Good luck
Andy

[Tubes4e4]

Hi Glenn,

Originally posted by porkchop61
I want to build a stereo "mini amp" using a 12AU7's as the power tubes. I'd like this to be an OTL design (just to save space), but PP is okay.

F.e., see the Hept'AU7 from Tim Williams.



Regards,

Tom

[porkchop61]

Thanks Andy and Tom! I'll read that thread.
I was trying to keep everything to 9 pin tube types, so I won't be using a 6SN7 but the idea is good.
I should have mentioned that I'll be using SS rectification (to save space).
I'm going to try and lay out a design using the design guides for the tubes I mentioned (12AX7, 12AT7, 12AU7).
Thanks for the response.
Glenn