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previous: Carlo Pipitone I'm going to do a general overhaul ... -- 2/29/2004 9:58 PM View Thread

Re: How to use the hum balance pot?

3/2/2004 2:32 AM
Re: How to use the hum balance pot?
There are two kinds of hum balance pot and some amps have both.  
One is the ground reference for the heater supply and that does indeed have no relation to tube wear or mismatching. Twiddle it for laest hum. It mainly affects the preamp.  
The other is a balance for the output tubes and very much depends on the tubes themselves. When you see Fenders with the bias pot wired as a balance rather than a straight voltage adjust, that is what it is for. Twiddle for least hum. A push pull output stage will cancel its own hum if the sides are balanced.

Carlo Pipitone Is hum affected by the main AC line? -- 3/2/2004 9:07 AM