Im about to buy a pair of polk db6750's, and I could use some help on selecting an amp. Right now I have the choice down to the infinity 7520a, and the Profile ap600. However I cant really decide on one as I know pretty much nothing about amps. Im sure there are better ones out there, and im definately open to suggestions. I would like not to spend over $170 though. Any help is appreciated, and thanks in advance.