I kinda disagree with that. I have a sunfire signatue bob carver grand cinema 2 amp. It powers 5 channel. let me tell you it is one hell of a powerful (425 wpc x 5) and very warm sounding amp it is bi-wired current/voltage. The rears are seldom used in the 7.1 config, but with certain material it's awesome, and makes 7.1 worthwhile. (you can make a good arguement for 7.1 not needed for most recoedings. I power my rears with the mono block amp. using the 5 channel amp for the imprtant stuff. I run a 7.1 set-up on a 5 channel amp, with the mono amp,, and it is great. P.S. Outlaw also makes a 7 channel amp, I think outlaw makes a very good amp at it's price point
