JBL L8400P 600-watt High Performance 12-Inch Powered Subwoofer with Digital Amplifier (Black) 12" cast aluminum woofer for powerful bass response 600-watt digital amplifier provides optimum power 50-150Hz continuously adjustable low-pass crossover Heatscape motor structure and Symmetrical Field Geometry provide powerful bass Gold-plated, 5-way bi-wirable binding post