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]

EAR V20

Hi,

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

Here's the link :-

http://www.diyaudio.com/forums/showthread.php?s=&threadid=94403


Good luck
Andy

 

[Tubes4e4]

Hi Glenn,

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.

An externally hosted image should be here but it was not working when we last tested it.

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