This thing Rocks guys. dont let the size of this powered sub fool you. I have it installed behind my seat and hits hard. I was skeptical at first but read all the reviews on crutchfield. Im very happy with it. plus im all about saving weight....
It has enough bass to shake the review mirror, Havent really tweaked it yet though.
Sound Ordnance™ B-8PT 120-watt compact powered subwoofer at Crutchfield.com
It fits perfectly behind the seat laying side ways. i can even reach my hand back and adjust the bass, freq and phase if need be.
Ryan