4x6V6on a twin OT

[wildeman]

I want tu use a Twin Reverb OT for 4x6V6. The OT has two sec. Tabs 4&8 Ohm. What speakerload should I use to stay in range.


Thanks a lot

[Firestorm]

KO'C shows an example of this in his first book. Using the 4-ohm tap (the only one on the stock OT), sine wave input and 4x6V6, he got 48W with a 4-ohm load and 48W with an 8-ohm load at Twin voltages. There's likely a tonal difference so it may be a matter of taste. You don't say what B+ you intend to run, but you'll be closer to "correct" with an 8-ohm load IMO.

[pops]

I built a tweed twin for a friend and it was way too loud so we put 6V6's in it and rebiased for them and it was wonderful. I would just do it and rebias. My plate voltages were not high tho so for me it worked great.

[tubeswell]

I want tu use a Twin Reverb OT for 4x6V6. The OT has two sec. Tabs 4&8 Ohm. What speakerload should I use to stay in range.


Thanks a lot

Depends of the impedance ratio of your specific OT. (Not all 'Twin Reverb' OTs are the same). If you have a couple of VAC meters and hook up a lowish (~5) VAC source to the secondary, and measure the resulting VAC across the ends pf the primary, you can easily calculate the Pr:Sec impedance ratio (it is the square of the Pr:Sec VAC ratio).

[cbass]

American 6v6s will handle the voltage. Bias a round 55%
I ran some for a while at 480 volts biased to 70% with no problems but it sounded just as good with less current

[Teleguy61]

I've had good luck with Chinese (Shu Guang) 6V6s hgandling the voltage, and they sound pretty good also.
Electro-Harmonix not so much, I've had multiple sets fail at Black Face voltages.

[wildeman]

So to stay close in range I have to use the 4 Ohm tab with 8 Ohm load and the 8 Ohm tab with 16 Ohm load? My plate voltage is about 450V with 4 x6L6.

[martin manning]

Correct.

[wildeman]

Thanks a lot guys!