600w/800w 10 Inch Car Amplifier Subwoofer Car Audio Slim Under Seat Active Subwoofer Bass Speaker Car Subwoofers Woofer Speaker - Subwoofers - AliExpress
Speaker-level inputs or line output converter (LOC)?
How to Connect a Subwoofer to Powered Speakers - Vanatoo
Amazon.com: Car Audio Amplifier Equalizer 7-Segment Auto Audio Graphic Equalizer with Front 3.5mm Auxiliary Input, Rear RCA Auxiliary Input and high Level Speaker Input, Adjustable subwoofer outputblack : Electronics