I have a Sony 6.1 receiver/amp and it works fine for movies and CD's from my DVD player (I use the component video inputs and digital coax) and pretty much anything I pipe through the computer to it (I use the 5.1 inputs and component video inputs the computer). The sound is good but not great, I don't think I am getting the 100 watts per channel the receiver claimed or for that matter anywhere close to it. My room is 20x26 I have 3 way pioneer 15" in the front with cerwin vega center and and 10" sub. In the rear I have 2 pair of 12" Criterion VI speakers rated at 50 watts. These rears have a good sound but even turned up all the way I can barely feel the woofer moving. I half expect this in the front with the 15's since I use the crossover in my sub (I get a lot of bass action out of the sub). My question is would adding a second power amp at speaker level fix my problem with sound in the rear? (I have put different speakers including the 15's in the rear and still too little sound) If I can do that without damaging the equipment what would be a good inexpensive (inepexsive on ebay) amp to buy mind you I will need one for the surround and the surround back when i get around to making that little change.

My second thought is upgrading from my sony str de597 to a yamaha rx-n600

I don't have a lot of money to spend on this upgrade and I am going to be stuck listening to with what ever decision I make for the next 2 years likely (I hurt my knee at work and know I will be off dicking around with them for the next two years)