Necro'ing an OLD thread but in case anyone is coming from Google via "best 300 subwoofer"
Here are some 2013 models to consider ... some are outside the $300 budget
$$$ BIC Acoustech PL-200 Hz: 22 - 200
$$ BIC America F-12
$ Dayton Audio SUB-1200 Hz: 25 - 140
$$$ HSU STF-2 Hz: 25 - 200
$$$$ Infinity Primus PS312BK
$$$ JBL ES 150P
$$$ Klipsch Synergy Sub-12HG
$$$ Klipsch Synergy Sub-10
$$$$$ Klipsch RW12D
$$$ Polk Audio PSW125
$$ Polk Audio PSW505
$$$$$ Premier Acoustic PA-150
$$$$ Velodyne Impact 10
$$$$$ Velodyne Impact 12
Legend: $ = roughly 100 USD; more $ does NOT automatically mean better!
Most of them are reviewed if you google: 2013 Best Home Subwoofer Reviews and Comparisons
The BIC Acoustech PL-200, or STF-2 are fantastic values if you can get one for less then 300 clams.
Edit: Added Legend, FR of PL-200 and STF-2, relative prices, Dayton Audio
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