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presence pot

11/3/1999 4:14 PM
peter	presence pot In the Fender blackface power amp, and the (similar) Marshall, the presence control is 25k. In my 'clone' amps (2 of them) with this circuit, the control doesn't do much until it gets to about 9, i.e. all the action is at the top end of the pot. This is perhaps unsurprising since the 25k pot (and cap)is paralleled by a 4k7 resistor. I used a linear pot. If I understand the circuit correctly, improving this would require the pot to be backwards-logarithmic, not regular logarithmic. (or am I confused?) So-- what is the taper of this pot, and is all the action at one end?? thanks.

11/3/1999 4:14 PM

peter

presence pot

In the Fender blackface power amp, and the
(similar) Marshall, the presence control is
25k. In my 'clone' amps (2 of them) with this
circuit, the control doesn't do much until
it gets to about 9, i.e. all the action
is at the top end of the pot. This
is perhaps unsurprising since the 25k
pot (and cap)is paralleled by a 4k7 resistor.

I used a linear pot.

If I understand the circuit correctly,
improving this would require the pot
to be backwards-logarithmic, not
regular logarithmic. (or am I confused?)

So-- what is the taper of this pot, and is all
the action at one end??

thanks.

Replies:

Dave H. q{If I understand the circuit corre... -- 11/3/1999 5:13 PM