A best bet is the Crossfire 10" Dual Voice Coil Car Subwoofer (pictured), model no. BMF1014, for $119.95. Coupon code "CF30" cuts it to $83.97. With free shipping, it's the lowest total price we could find by $62. It features a 20Hz to 250Hz frequency response, 800-watt peak power handling, and more.