[_paralyzed_]

lets remember his setup, he has 285 watts coming out of his reciever for a sub, so that means he doesn't need a plate amp, and yes, a powered sub is the easiest solution. I assume your kicker is 4 ohms(most car subs are) so you've proven your reciever can handle 4ohms. you could step up to a 15" woofer, or run two 12" 8 ohm subs in parralel, a couple more efficient speakers splitting the power would give you more volume. I guess we need more info. Do you want a cheap solution, an easy solution, or the right solution? I personnaly would put the kicker back in the car, run no sub off your reciever allowing it to only run mids and highs, and get a big ole 15" powered subwoofer, a cerwin vega, with the red surround, that will shake sh@! off of walls