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Vintage threads from the first ten years

Volume control Tone

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5/29/1997 7:23 PM
Francis Geraghty	Volume control Tone When I reduce the vol. on my guitars PRS or Strat Ultra, I loose the Top end. I have a Morley Wah/Vol which has same effect ( on used batteries) I heard about a resister in the guitar - Please explain. I tries a Triaxis today and this problem did not seem obvious. Could it be my amps, or is it the guitars??? Regards , Francis

5/30/1997 7:15 AM
Dave Harris	HF loss is caused by the capacitive loading of the cables/effect/amp on the guitar vol pot. You could try fitting a 1nF cap in parallel with a 150k res between the wiper and CW end of your guitar vol pot. It helps but it is not perfect. The above values work quite well with a strat with a 250k vol pot. DH

5/30/1997 7:46 PM
Francis Geraghty	Thanks, but over my head!!! I did not experience this tone loss ( high freq) on the Triaxis. I use whirlwind leads as I thought they were best. So is it the Amp, Guitar, effects (replifex) or leads ?? Regards Francis

6/2/1997 3:46 AM
Dave Harris	Sorry about the confusion. I am an electronics engineer and lousy guitarist. I wish it were the other way around ! DH

5/31/1997 9:37 PM

Francis, it's like this: Your volume pot has three
connections. One is a sort of input, one is a sort
of output, and one is soldered to the case
(ground).

Take a capacitor with the value of .001microfarads
and solder it across the two leads on the volume
control that are being used (have wires, not
soldered to the pot's case).

When you turn down the volume, the highs will
bypass through the cap to the output, so the tone
will be bright. This is exactly how a bright switch
works on a Fender amp (different value pot tho).
Ever notice that the bright switch only works when
the pot is turned down from full? At full,
everything passes through the pot, so bringing
the cap into or out of the circuit wont matter.

Got it?

6/1/1997 8:36 PM
Francis	Thanks Charles, I get it, and will do this mod. How come expensive guitars d'ont include this. Is ther a down side to it? Francis

6/2/1997 5:56 AM
Dave Harris	I guess it’s not on all guitars because it’s not a perfect solution. Some people don’t like it. If you just use a cap then you may end up with more top end as you turn down the vol. If you get this try fitting the 150K resistor as well. DH

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