If you want it to hit hard, go for a single 15", cause single 12" may not be enough. Instead of Kenwood, I would pick something like a Kicker L5 sub, and it does not need to much amp power to get loud. There are some nice deals on Kicker L5 subs, and Kicker amps like ZX750.1. If you get this package, you'll be good to go for some window rattling.