Guitar Gear Forum

is there a way to run an led off ac heater voltage? I'm think if all else fails I'll just build a rectifier.

Yep. Its pretty easy. There is a discussion of the various ways to do this on http://music-electronics-forum.com/ but its currently down. Really a full blown rectifier circuit is overkill and it will inject a lot of rectifier hash into the heaters which will be picked up by any stray capacitance floating around so I'd avoid that. A single diode and cap will do the job along with an appropriate dropping resistor.

what sized cap and what type of diode?

A 1n4007 will do fine. Overkill but cheap and easy to find. 4700uf should do it fine.