I just got a 10" Polk Momo subwoofer, powered by a 300 watt x 1 bridged Blaupunkt amp. Compared to all the Alpines and MTX and other more common brands ive heard, these handle the power you send to them extremely well, and dont distort no matter how loud you turn up the volume. Its clean and punchy as all hell, and keeps its composure very well in all sorta of music....for SQ i think it would be hard to beat.
I've found that it compliments my 8 speaker stock setup and headunit very well, and gives me just the right ammunt of bass. It might not have the massive thump of something geared towards maximum SPL's, but i think its a great setup for the money i paid. >

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