Hopefully you guys can help me out here since you were all pretty helpful with my last question. Christmas is coming and with Christmas comes money and presents, so here I am thinking about what to upgrade in my budget HT system. I previously had a cheap-o Sony 5.1 system that I'm no longer using. Right now I have a very simple, cheap 2.1 system: Technics SA-DX950 Receiver (I'm going to get rid of it sooner or later, but I don't think this is a major weak point, correct me if I'm wrong) Polk R20 Bookshelves (given to me as a present, they sound much better than the Sonys so I'm planning on keeping them for a while if only as rears) Aiwa TS-W150 Subwoofer (I don't like it very much at all, so it's something I want to replace as well) I listen to about 50% music and 50% movies, so I'm really not at all happy with my setup - but being a poor college student on a budget there's not a whole lot I can do about it right now. Since Christmas is coming up, though, I figure I can upgrade or add at least one component and that's what I need advice on... As reference I'll have about $400 for audio stuff once Christmas is over. Would it be wise to stick with Polks and get a center channel speaker and maybe a subwoofer or should I go right ahead and use that money to grab new mains and put the polks in the rear? I've been listening to music a lot lately so I'm seriously considering picking up new mains. I'm going to take a trip down to my local audio shop to check out prices, but what brands should I be looking at in the $400 price range? Oh, and if any of you happen to think I'd notice a bigger difference with a new receiver or a new subwoofer let me know. I'm a newb when it comes to this stuff so I'm just looking to learn as much as I can before I put down any money. Thanks!