A while back, I described some problems with trying to use treble bleed on a guitar with multiple volume pots. When turning down one volume pot, that pickup retains brightness, but the other pickups get duller. In the diagram at right, with middle and neck pickups in a blended switch position, the middle volume is up full and the neck volume is turned down. The middle pickup high frequencies have a path to ground through the neck treble bleed cap. More
Guitar Treble Bleed
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Update Feb 4, 2011: I wrote up a number of ideas for solutions in this blog post.
Before plunging into the details, here’s the abbreviated version: treble bleed caps don’t work well if you have more than one volume pot connected together. For example, with two pickups and two volume pots with treble bleed, turning down one will result in loss of high frequencies in the other. Not good! More
In part one of this, video I explain what treble bleed is, and how to evaluate and select the right cap. I demonstrate my G&L ASAT III which has a treble bleed cap on the master volume, and I compare that with my Epiphone Riviera P93 which has no treble bleed caps (yet).
The caps I tried are (as shown left to right): Silver Mica 100pf, 390pf and 1000pf, a tiny 1000pf ceramic cap, and Sprague Orange Drop (polypropylene) 1000pf, 3300pf, and 6800pf.
The tolerances on the caps are a bit all over the place. I measured the 1000pf caps on my DMM and all were closer to 1250. The 100pf silver mica was over 250! This is assuming I can trust my Mastech DMM.