ClassicTone # 40-18088 with four 6v6 tubes?

[dinkotom]

Is it ok to use four 6v6 tubes with ClassicTone # 40-18088 transformer?

[dinkotom]

at the moment, it's a 30 watt, 2x5881 amp, (sort of cross between fender super 5d4 and magnatone 260), but it has 4 output sockets (long stroy ). Plate voltage is around 400V. If that's at all possible, I thought I'll just put four 6v6 in it and adjust the bias circuit. Kinda love the 6v6 tubes lately.

[FUCHSAUDIO]

4-6V6's is essentially 2 6L6's: Half the heater current, twice the Plate impedance, like RCA planned it that way .
If you set it up for Half power, you move the tap accordingly.

[martin manning]

At 400V, 4x 6V6 would like around 4k primary, so the 6k you have is not ideal. It will work, but the primary load is a bit high, and miss-matching down to 3k is too low. Not really great for 2x 5881 either, they would also like 4k. Dropping the screen voltage by increasing the screens to 1k or 1k5, or adding a shared 1k, would help. You could put a 4-ohm load on the 2.67 ohm secondary and get a 9k primary, which would be pretty good for 2x 6V6.

[dinkotom]

Got it, thanks guys!

[Guy77]

You could put a 4-ohm load on the 2.67 ohm secondary and get a 9k primary, which would be pretty good for 2x 6V6.

Thanks for sharing this information Martin. I always wanted to experiment with different Primary values on output transformers

Cheers

Guy

[roberto]

6k Raa at 400V can be ok for a quartet of 6V6 to get around 35W if you keep screens around 270V (you hit g1=0 with plate at around 70V).