PA Speakers for Parties


Hello,
I am brand new to this whole scene. I am in a fraternity and got elected to run certain aspects of our parties. What we need are PA speakers (our old ones broke) They need to be self powered, I am not really sure what exactly a decent setup would be but parties are generally in a huge room with close to 100+ people. We had two older speakers that managed for a few years before biting the bullet. Anyone have any leads they can give me or tips, brand new to this whole thing.
matthewcarnali
First question, what's your budget?
Second, what equipment will they be used with?
There's more questions but, answer these two and folks will have a little better idea of what to recommend.
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Thanks for the input, I literally have no equipment, its mostly to play ipods with playlists and such. My budget is around $300.
I think your budget is unrealistic.. Big room ( get the exact dimensions) lots of people.. playing dance music.. you're gonna need some real stuff.. Google is your friend, but here's a link to get you started.. might even want to give them a call... http://www.sweetwater.com/shop/live-sound/pa-speakers/