AMPERE AUDIO 4000 WRMS SUB LINE TOUR / REVIEW / FLEX TEST! - YouTube
How to Match Speakers and Amps | The Master Switch
Amazon.com: Fosi Audio M03 200 Watt TPA3255 Subwoofer Amplifier Mini Mono Channel Audio Power Amp for Home Theater Full-Frequency and SUB Bass Switchable with 32V/5A Power Supply : Electronics