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Re: tone circuit

9/27/2000 8:07 PM
Riff Ron
Re: tone circuit
What does the 220K resistor do?
9/28/2000 7:30 AM
Preben Hansen

Both RG and AMZ has some articles about pots on there sites that explains what you can do to alter the taper of a pot.  
About the cap, that gives more treble at lower volumes: I use a 680pF on my strat (neville) copy, in parallel with a 250K resistor. This works very fine on this guitar.  
Regards Preben.
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9/29/2000 3:48 PM
Ian Anderson
suggested 'R' and 'C' values for humbuckers?
Anyone used the treble bleed mod on a LP type guitar? - what values work well?  
... Ian
9/30/2000 3:28 AM
Steve A.

    I've been using a 180pF mica cap in my LP... and then I found out that PRS was using the same value. I find that it has a "true" sound to it as you back off the volume control (a cap like the .001uF on a Tele will enhance the highs as you back the volume off).  
    As for 220k resistors between the ungrounded terminals of a volume pot, I've used them on all of my guitars but since reading the articles on them it seems like it would make the taper more linear... or maybe more like a log/antilog taper?  
    Lots of people are looking for a guitar amp that will clean up as you turn the guitar volume pot down. I'm not sure if the the 220k resistor helps or hinders this! Any thoughts on that?  
Steve Ahola
9/30/2000 12:02 PM
Ian Anderson

Cheers Steve, I'll try that out at my next rehersal - next gig is a month away :(  
... Ian  
P.S. Anyone know how to get all the different smiley/grumpy faces, they're great fun! (I know, I should get out more etc...)
9/30/2000 4:13 PM
Ed Rembold

I've since we last "talked", I've done alot of testing with this- and the answer is "it depends".  
the 220K, on a 500K audio pot, does make the  
taper more "linear". with the 220K in place, you  
lose the big "Ramp" in volume, when turning the  
pot from 8 to 10. But, you gain a more useable  
taper when turning down from 8 to 4.  
Here is a little chart which may help-  
(note, this is only for 500KA pots)  
100pf/500k resistor-good 8/10 ramp, only slight  
loss in highs turning down to 1.  
220pf/220K resistor- No 8/10 ramp, clean taper, with  
even freq. response all the way to 1.  
500pf (or larger cap)220K resistor- Now, tone gets  
brighter as you turn down to 1, this may be  
desirable for some, but not to me, to each his own.  
so, if a person likes to "clean up" his distortion  
with his guitar volume pot, you can see that retaining the 8/10 ramp Is desirable! clip that  
220K and put a 500k in its place.  
Ed R.
10/1/2000 6:53 AM
Eric H

Great work, ED. FWIW, I've never used the resistor, just the cap (learned this trick a LONG time ago) and have been thinking about adding a resistor to fool around with the taper, I'll give it a shot.  
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