the creative inspire series is an awesome 5.1 set up which has plenty of bang for the buck. i would say that the most important thing for good quality sound is a good sound card. i have the creative sound blaster x-fi xtreme gamer ($100) and i really cant explain in words how awesome it sounds. if you combine a good sound card with a 5.1 surround set up (i.e. Creative Inspire T6100,$80), you should be good to go. hope this helps.
I need a new pair? Any good suggestions on a set less than $100 (I'm not looking for amazing sound quality just something with a lot of bang for its buck.) Should I get a 2.1 system or a 5.1 system?

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