Infinity amps arent bad, but they have a low signal to noise natio, and tend to have pretty weak filters. I have an elemental desigins 4 channel amp, which has a Signal to noise ratio of 103 db, where infiinty has 81. For every 3 decibles, the sound quality doubles. It doesn't really make a hugh differenec, but my speakers have no hissing whatsoever, and i like it that way. Elemental Designs makes great amps, but are a little pricey. Try alpine