Polk Audio PSW505 12″ Powered Subwoofer for $209.99 after promo code SPEAKER572. Shipping is $4.99, so the total comes to $214.98 shipped. Here is a screenshot for your reference. It features a 300-watt continuous power amplifier, 23Hz to 160Hz frequency response, auto on/off, and more. This subwoofer usually sells for about $249.