Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: 12AX7 on April 27, 2013, 08:18:22 am

Title: running 6V6 in a EL34 designed amp
Post by: 12AX7 on April 27, 2013, 08:18:22 am
I have a amp i built with a output very close to the same as a 2204. I've been running 6V6 in it lately, JJ's to be exact because they supposedly can easily handle the 440 plate voltage. I bias them to about 18Ma and they sound really good. My question is, i run them on the 8 ohm tap with 8 ohm speaker and the POT is 3.2k. I know i should run it on the 4 ohm tap which would be much closer to thier 8k spec. (something like 8k isn't it?) But it sounds much better on 8. Will this be risky and if so what about when running it at home levels? (master fairly low, maybe 9:00 at most)
Title: Re: running 6V6 in a EL34 designed amp
Post by: HotBluePlates on April 27, 2013, 09:11:51 am
... i run them on the 8 ohm tap with 8 ohm speaker and the POT is 3.2k. I know i should run it on the 4 ohm tap which would be much closer to thier 8k spec. (something like 8k isn't it?) But it sounds much better on 8. ...

Then run them on the 8Ω tap.

If you play the amp cranked, take a peek in the back and be sure the tubes aren't redplating. If not, then there's nothing to worry about.
Title: Re: running 6V6 in a EL34 designed amp
Post by: alerich on April 27, 2013, 09:14:38 am
Here's an old thread on a similar topic that has some good information:

http://www.el34world.com/Forum/index.php?topic=6725.0;wap2 (http://www.el34world.com/Forum/index.php?topic=6725.0;wap2)

I think it would be okay if you monitor the amp like HBP recommends.

Title: Re: running 6V6 in a EL34 designed amp
Post by: 12AX7 on April 27, 2013, 09:19:11 am
Thanks, i will then. They're biased cooler than i see others running them so i assume that helps.
Title: Re: running 6V6 in a EL34 designed amp
Post by: HotBluePlates on April 27, 2013, 09:21:22 am
20-22mA is where I had my '67 Princeton Reverb when I owned it. Your bias seems similar, especially if B+ is higher than it was in the Princeton.