So I'm finally going to build the rack for which I've had 2 preamps and a power amp sitting around for about 5 years. Basically one preamp will be clean and the other distorted and I'll a/b to input into either. The problem is I want both to plug into the 1 input power amp. I'm electrically retarded but I have seen strange things happen in these situations. If you use a standard Y 1/4" from radio shack to plug 2 guitars into one amp and one turns their volume off then the other one is muted too, meaning that both players pickups are actually feeding into the other one's guitar (bizarre). Would something similar happen if I tried this with 2 preamps into the same input jack of a poweramp? I would really like to be able to do this so I can a/b right after the guitar. If I a/b after the preamps it requires two extra cables coming from the rack and tap dancing on overdrive pedals and shit to get a clean tone. Actually if anyone knew of a rack stereo EQ with a mono output that would also solve the problem.