Whats goin on. I;m havin a problem with my car audio system. At medium volume levels the bass from my sub sounds great but when i crank up the volume it gets real sloppy and doesn't sound clean at all. I have a Kenwood KAC 7202 2 channel amp which puts out 460 watts bridged. I have one polk dx 12 inch sub in a sealed box. The sub can handle 400 watts max and is 4 ohms with a single voice coil. I have all this in a honda pilot SUV. I was thinking that maybe i need to upgrade my subwoofer. If thats the case could someone suggest a sub that would sound good with my amp. I really don't know too much about this stuff. Any suggestions or advice would be appreciated.