dberning wrote:
I have found that as little as 1/4 mA can affect transformer saturation and distortion in the bass and sound in general. That is why I aim for the lowest bias current that is acceptable for crossover distortion because it is easier to control 1/4 of a mA out of 5 mA than it is to control 1/4 mA out of 30 mA. It is the absolute difference, not the percentage here. Also, a separate bias pot should be installed for each output tube(s) for the pull and the push. This is also one of the driving factors for me to have autobias, but it is tricky to do for class A-B or class B.
--David--
Thanks, David. I have one bias pot for each channel. I have noticed that when I adjust the bias pot on one channel, it affects the bias of the other. I think this is because my negative bias supply is not regulated. If I install 4 pots, won't it be even more difficult to set my bias correctly? Should I regulate my bias supply to get around this?