The VRX918SP was designed specifically for use in arrays with the VRX932LAP Line Array speaker and VRX-AF Array Frame. In addition it may also be used in arrays consisting entirely of VRX918SP subwoofers. At A Glance: Built-in JBL DrivepackDPC-2 amplifier module designed by Crown provides 1500 Watts of peak Power DSP based resident input module provides system optimization, EQ and crossover functionality 18 inch, 2268FF dual voice coil, neodymium magnet Differential Drive woofer for high-power capacity and  light weight Integral rigging hardware for simple connection of enclosures and optional array frame. 20 mm threaded pole socket for solid, secure satellite speaker mounting Large port area for reduced distortion POWERED BY CROWN Designed in cooperation with Crown International, the ultra compact, high-power JBL DrivePack DPC-2 amplifier module features Crown??ç?ûs Class D digital power amplification circuitry. DBT (Dual-Bridged Technology) directly links discrete amplifier channel outputs to each voice-coil in the Differential Drive loudspeaker. The DPC-2 incorporates Crown??ç?ûs BCA (Balanced Current Amplification) Class-I circuitry with temperature compensated modulation and state of the art feedback circuitry. An extraordinarily efficient passive cooling system eliminates noisy fans. DIFFERENTIAL DRIVE WOOFERS Sound reinforcement professionals constantly ask for more power but less weight so JBL designed the VRX??ç?ûs drivers with much less weight than comparable drivers and yet significantly increased its power handling and output. QUICK CONNECTIONS The setup for VRX900 powered speakers is fast and easy. Simply connect up to three loudspeakers together by looping the power and audio cables from one unit to another. One power cable and one source cable can drive the entire system. DURABLE CONSTRUCTION VRX900 Series enclosures are constructed with premium quality birch plywood. Coated in JBL's rugged DuraFlex finish and heavily braced the systems are extremely ndurable, not to mention rigid and resonance free. The heavy-duty steel grilles are internally lined with acoustically transparent foam to provide additional driver protection. Condition Note: This Subwoofer was an unopened customer return. It is verified to be in New Condition & Includes the Manufactures Warranty.