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Volume pot and high end


 
11/14/2005 1:34 PM
harvey Volume pot and high end
How can I stop my high end from rolling off when I reduce volume? Any recomended mods?  
Thanks.
 
11/14/2005 2:12 PM
Ian Anderson
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play with various cap values between the 'top' of the pot (i.e. the outer lug that is not grounded) and the wiper (middle lug). anything between 100pF and 500pF seemed to work for me.  
 
... Ian
 
 
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11/14/2005 2:27 PM
RedHouse
And to keep that mod from sounding quacky add a resistor in series with the cap, a value of about 1/2 the the pot you are attaching it to.  
 
For a 250k pot, use a 130k resistor.  
For a 500k pot, use a 280k resistor.  
 
(unless you like that quacky sound, many do, if so leave off the resistor)  
 
Some, including certain Fender guitars, add the resistor in parallel with the cap ...but... that modifies the taper of the pot and I use decent CTS pots and don't like the taper messed with when adding treble bleed.
 
11/16/2005 1:24 PM
Harold H
Here is a link to wiring diagrams from the Kinman (PU) site. There is an example of a roll off reduction circuit.  
http://www.kinman.com/html/toneWorkshop/tone.htm#WIROGRAMS  
 
Harold
 
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