Monoprice Monolith 13in THX Ultra Certified 2000 Watt Powered Subwoofer Massive Output, Low Distortion, For Studio and Home Theater Systems Audio / Video Accessories - Newegg.com
Emphaser M10 Monolith 25 CM Subwoofer 1 x 4 Ohm 200 Watt RMS 25 CM/10 " | eBay
Amazon.com: Monolith 13 Inches THX Ultra Certified 2000 Watt Powered Subwoofer Massive Output, Low Distortion, for Studio and Home Theater Systems : Electronics
Amazon.com: Monolith 16in THX Certified Ultra 2000 Watt Powered Subwoofer (Matte Black/Painted) Low Distortion, for Studio and Home Theater Systems : Electronics
Monolith M-iwsub82 Dual 8in In-wall Subwoofer| Passive, Paintable, Easy Install, Adds Powerful Bass To In-wall Or In Ceiling Home Theater System : Target