A Hifonics **LIKE THIS** would be one of the few budget amps I would recommend! **This** Crunch amp would probably do the job too!
Then again, if you are really cheap, and want to keep the Kenwood theme going, you could always get **THIS** OR **THIS**. Another plus is that you don't have to worry about overpowering your subwoofers with the Kenwood amps because they are only good for about 650 watts RMS.