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previous: tony which resistor "cuts" more highs? 220K or 470K? -- 3/10/2003 6:43 PM View Thread

Re: which resistor "cuts" more highs? 220K or 470K?

3/11/2003 5:00 PM
Mark HammerRe: which resistor "cuts" more highs? 220K or 470K?
When the next stage in line "looks" at your guitar, it "sees" several paths to ground. One of them is the volume pot itself, another is the tone control (via a cap), and the third is the pickup. If the pickup's impedance is noticeably lower than the pots, for a variety of reasons the next stage will "see" more high end from the pickup (assuming it can deliver such high end).  
 
The extra high end that is preserved and "seen" may be pleasing to some players, and annoyingly brittle-sounding to others. The tradition has been to use 500k pots for humbuckers, to hang onto what little top end they have, and 250k pots for single coils, to tame the considerably greater top end they have. If you drop your HB's volume pot down to 250k, you will "hide" a certain amount of whatever excessive top end that pickup is capable of delivering.  
 
Alternatively, since caps come in many more values than pots, and since you may like your current pots a lot (and also risk damage in trying to remove them), consider simply adding some caps. A small value cap between the pot input and ground will shunt high end to ground in the manner of an additional custom-tuned tone control. Choose the value wisely and you'll tame the top-end fizz while retaining the slightly lower-frequency bite.  
 
The cap used should obviously be of a much smaller value than your tone-control cap so that your existing tone control/s continue/s to work in an audible manner. If the current tone cap is .02uf, consider something in the neighbourhood of a .001-.0015uf cap for starters, making the value smaller if it robs too much high end and larger if it doesn't tame enough.  
 
Note that the sonic advantage of a laboriously-chosen pot value pretty much disappears once you turn down the volume pot to 7 or less. The cap trick I suggested will function almost independently of where the volume pot is set to. The other nice thing is that it is easily reversible by unsoldering the cap.