Per suggestions on this board (thanks guys!!) I bought a used PPI PCX4125 amp to power my tower speakers. Got one question though, didn't come with a manual and can't seem to find one online. All the connections and adjustments make sense except the RCA's. Can anyone tell me which of the 3 sets of RCA's is what?? I'm sure I can figure it out by connecting things, but knowing before installing would sure be helpful!! Thanks!!