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Volume control Tone

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.  
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 ??  
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 !  
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  
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

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?  
6/2/1997 5:56 AM
Dave Harris

I guess itís not on all guitars because itís not a perfect solution. Some people donít 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.  

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