Best SS Amp with tight clean bass

I have a pair of Polklsi15 speakers. The problem is they have a great tweeter and mid, but the bass is very ragged and loose. I want to match a good tight amp on the lower to try to aleviate the problem somewhat. Next i will mess around with the cables.
P.S. I just bought the new Rogue Audio Cronus Int amp and it is absolutely wonderfull. Any responses on the above would be appreciated.