I am making my own jem and need to get this straight before I do the electronics.
Im pretty sure he uses 500k, but not 100
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OR 50 with 4 x 12
Gassing for ibanes airplane flanger
For the high-output humbuckers, I'd be willing to bet 500k also.
The world doesn't revolve around you. If it does, beware. You're probably about to pass out drunk.

The 19 year old who knows his stuff. Most of the time.
Capacitor =/= potentiometer.

I did a quick search and did not find anything. You could, however, buy a few different quality caps and test it out yourself.. I'm willing to bet that Vai uses .022mfd or less caps. I say this because he uses high-output humbuckers, which generally calls for a lower microfarad rating. Buy a couple of different capacitors and try them out.

EDIT: http://www.jemsite.com/forums/f15/values-of-pots-and-capacitors-33793.html?highlight=capacitor

There's a bit of help, and a great website.

By the way, I was right about the .022mfd! :P
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Last edited by philipp122 at Dec 2, 2009,
His guitars are pretty much stock jems with the exception of the sustainer and the trem system.