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previous: dmot someone recently advised me to repl... -- 6/16/2000 2:37 PM

Re: variable bias? what's that and how to make?

6/16/2000 2:58 PM
Benjamin	Re: variable bias? what's that and how to make? DMOT, Basically you would be replacing a fixed resistor in the bias supply with a potentiometer to adjust the negative voltage to your power tube grids. This is just an easier way to service the amp when retubing. There is no performance increase........ just convenience :>) Look at the transition in some fender blackface amps from fixed resistor to potentiometer. that should get you steered in the right direction. Benjamin

6/16/2000 2:58 PM

Benjamin

Re: variable bias? what's that and how to make?

DMOT,

Basically you would be replacing a fixed resistor in the bias supply with a potentiometer to adjust the negative voltage to your power tube grids. This is just an easier way to service the amp when retubing.
There is no performance increase........ just convenience :>)

Look at the transition in some fender blackface amps from fixed resistor to potentiometer. that should get you steered in the right direction.

Benjamin