The LSR6312SP powered subwoofer is based on a 12" woofer with JBL's patented Neodymium Differential Drive NDD and 250W of power. An integral bass-management system provides all the features you need for multiformat surround production: LCR and Direct LFE inputs, summed output for chaining multiple subwoofers, -4dB alignment setting, and JBL's RMC (Room Mode Correction) system. RMC Calibration Kit included. This JBL speaker is the perfect low-frequency partner for a set of JBL LSR6328Ps (sold separately).