Behringer VQ1500D 500W 15 inch Powered Subwoofer | Sweetwater
Stage Right by Monoprice LM15A 1000W 15in Powered Subwoofer Speaker with Class D and DSP - Monoprice.com
Amazon.com: Audioengine S8 Powered Subwoofer Speaker - 250W 8-inch Home Subwoofer with Built-in Amplifier and Dual Audio Inputs for Home Speaker System (Black) : Electronics
Trevoce Triple 10" Active Subwoofer | Outdoor Speaker Depot