I have had very good luck with Carvin eqpt.(Carvin.com)It is USA made and moderate in cost, and they can provide a full system from DJ or other mixer, EQ, limiters, and amps and speakers. The equipment is probably not quite as good as JBL or Crown in the noise,/distortion department, but in a skating rink no one is going to be complaining about the "imaging" not being perfect! Also construction is lighter, but in a fixed system, this won't matter