A large sub in a small enclosure, this 12-inch woofer from Alphasonik has a 4-ohm impedance, 92 dB sensitivity and can hit frequencies as low as 26 Hz while handling a rated 500 watts RMS.

The Q Sub series woofers include the 8-inch Q SUB80, the 10-inch Q SUB100 and a 12-inch model, Q SUB120, range from $900 to ...