Amazon.com: Monolith Powered Subwoofer - 15 Inch with 1,000 Watt Amplifier, THX Certified, Ideal for Professional Studio and Home Theater : Electronics
Monolith M-15 V2 15in THX Certified Ultra 1000-Watt Subwoofer with Built in Amplifier | Reverb
Upgraded to a Monolith 15” THX! : r/hometheater
Amazon.com: Monolith 16in THX Certified Ultra 2000 Watt Powered Subwoofer (Matte Black/Painted) Low Distortion, for Studio and Home Theater Systems : Electronics
Amazon.com: Harmony Audio HA-ML152 Monolith 15" Car Stereo Competition SPL Sub 3200W Dual 2 Ohm Subwoofer : Electronics