The thought of more channels for my HT sounds pretty sweet but i have a few questions. Is 6.1 three front channels (L,R,C) and three rear channels (L,R,C)? I have a 5.1 setup right now. Do you need a center speaker for the rear center or will any good ole speaker work? Where are the 7 channels for 7.1 located? Is it three front, 2 rear, and 2 on the sides?