Amazon.com: ZK-1002T Bluetooth 5.0 Amplifier Board 2.1 200W HiFi Subwoofer Audio AMP with Treble and Bass Control BT and AUX Inputs, DC 9-24V 2.0 Channel Stereo AMP Module for DIY Speakers, Password
DIY 1000 Watt Subwoofer Amp - IBUILDIT.CA
How to Make a Subwoofer Amplifier : 6 Steps - Instructables