I've read quite a few posts on this and other forums about going the halfway route regarding separates, i.e. buying a decent 5 channel amp and pairing it with a cheaper AV receiver to do all the processing (as opposed to a more expensive Pre/Pro). My question is, what determines the quality and character of the sound (besides the speakers, of course)? Is it the Amp, as I've read many people state? Or is it the Preamp with all its processors and so forth? Is it both equally? When somebody describes the particular character of a mid to high level receiver (warm, bright, cold, dull, etc) are they most likely describing the sound of apm stage or preamp?