I'm going to purchase the Sony STR-DH720 945W 7.1 Channel 3D Receivertoday. I have the whole video quality up to par but now I'm trying to get my audio quality up to par. Currently I have 5 speakers that came with my old "cheap" system (2 surround back, 2 surround front and 1 center). i dont know how many watts these speakers can handle considering the previous receiver has 5.1 channels. should i purchase new speakers or additional speakers? any recommedations? sidenote: I dont know any details regarding the old paramax receiver, it was handed down to me over 4 years ago.