A friend of mine is trying to wire a guitar according to an old GP article which shows how one of Jerry Garcia's custom guitars was wired.

The wiring somehow allows the guitars volume to be changed without decreasing the signal level going into outboard effects and thus affecting their tone (or something like this).

The article mentions a device in the circuit called an "op-amp" (operational amplifier), but lists no identifying part no. or mfg.

Anyone shed any light on what the proper component is? Thanks.

Ah jeez, somehow talk your friend out of this before he screws up a perfectly good guitar.

Jerry was off into a bunch of bizarre stuff after he quit playing his white strat live. This wiring "scheme" did indeed involve using an op amp as a splitter (Editor Note: if your friend doesn't know what an op amp is, he hasn't got a prayer of pulling this off, he is truly clueless, op amps are among the most common SS devices out there), he also ran a buffered output out to his pedals, then back into the guitar so when he rolled the guitar volume back, he was also lowering the "effected signal."

This misguided scheme involved miles of extra wiring, proprietary connectors and, in short, a whole bunch of BS that was completely unneccessary. Just use a freakin' volume pedal instead.

Just my .02, but Jerry's tone was the worst on the planet when he started doing this BS. It was much better during the "Live At The Keystone" era when he'd just plug his strat into Fender Twin Reverbs.