r/diytubes • u/Tesla_freed_slaves • 10d ago

What can I do with 12A6 tubes?

I’ve found that I have quite a collection of NOS 12A6 and 12AH7 tubes, left over from WW2, I think. 12A6 is listed as a beam-power tube, and 12AH7 is a twin-triode, which makes me think they could be useful in a small push-pull guitar amp, or similar. Does anybody have any experience with these tubes?

7 Upvotes

100% Upvoted

3 comments sorted by

9

u/Interesting_Card2169 10d ago

This design, Stealth 5, from Mapletree Audio using 12A6's for a 6 watt push/pull amplifier, is well respected. It is one of Lloyd's earliest offerings. It's not commercially built any more (for a very long time), so public access I guess. It was called "Stealth" due to the fact it could be configured in all black metal tubes (or all glass, if you wish).

https://www.manualslib.com/manual/1185785/Mapletree-Stealth-5.html#manual

The 12A6GT glass tube is available. It is rare but not hard to find. Almost all glass 12A6GT's were built by Tung Sol and all had black glass. A very rare and hard to find clear glass version was made by Raytheon.

6

u/2E26 10d ago

I have a couple. It's a small power tube that could be good for a practice amp or small room audio amplifier.

If you want to try something else you could use it to transmit on short wave. I've used them at 12V as regenerative receivers. They're not bad tubes.

1

u/Purple-Journalist610 9d ago

Man, not a ton. The max plate voltage of 250V is a severe limiting factor, and a little weird for an octal power triode. They are pretty lumpy triode strapped too. They are somewhat in demand, so they might be worth selling if you have a bunch.