I'm starting to upgrade my home stereo/AV system and am looking at the Marantz receivers. The Marantz 5600 is $600 at Cambridge Soundworks and the Marantz 7500 is $1000. Is the 7500 worth the additional $400? (Is there a 7600 coming soon?) Is the extra 15 watts between the two noticable? My living room is approximately 450 square feet, with aproximately a 12 foot ceiling. I would like multi-room capabilities down the road. In selecting a receiver, I'm focusing more on a good musical sound, than HT. This will be connected to my HT (which is just a TV, DVD, CD, tape deck and Dish receiver). The way it sounds playing music is more important to me (if it sounds great with music, the HT sound will be good enough). Is there any difference in the power supplies or build quality between the two models? (I would love to get the 8500, but it's out of my price range right now.) I currently just have an old 70s vintage Pioneer SX-790 receiver, connected to some inexpensive speakers. I'll be replacing the speakers later, but I want to start with a good receiver. (I guess any new receiver will be an improvement!) Thanks for any help!