That depends on what kind of music you want to make. Here are my thoughts: Assuming you're into the rap/hip hop thing, you'd be well served by E-MU's Mo'Phatt rackmount module or a used MP-7 Command Station. If you're into electronic/drum n' bass stuff, check out E-MU's XL-1 Turbo module or a used XL-7 Command Station. These are BY FAR the best value in terms of out of the box professional sound quality and features for the money. Get yourself one of these units and you wll not be dissappointed. You can do some seriously sick sonic tweeking with the Proteus synth engines. Very powerful and user friendly! I own an XL-7 and love it. If you're on an even tighter budget, pick up one of those little Roland SH-32's. One of the best $250 I've ever spent.
http://www.novamusik.com/search.aspx?ty ... keyword=60
http://www.novamusik.com/search.aspx?ty ... keyword=26
don't forget a decent controller
http://www.sweetwater.com/store/detail/TMK49/
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