I was surprised to see Mac recommend the Logitech 3-piece system. I have several of this type and I love them. I have one on my TV, others on each PC. I uses them for gigs in the smaller rooms. They give the best reproduction of the stereo voices on my keyboards of any keyboard amp I have tried, hands down. I like what they do with vocals, a lot.

Most are Logitechs of various sizes, but I have one from Boston Acoustics which is very nice. Logitech's customer service is outstanding.

NOTICE the speaker cones in the picture that Mac gave the link to. They look like concave silver disks with nothing at the central axis. I dont know what you call cones of this type, but I like them. I have a couple of pocket size battery systems like this type that I got at a Target for $10. They are great for plugging into an ipod or laptop. The sound quality is really very good for one or two people listening close up.

Flatfoot sez: Call me when 'Talent-in-a-Box' is ready to ship! -- [8{>

Got some tunes on You Tube:
http://www.youtube.com/user/flatfoot50
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My BiaB lesson site:
http://jdwolfe0.wixsite.com/learnbiab