The VRX918S is a compact, high power suspendable subwoofer system containing a 2268H neodymium magnet, patented Differential Drive, 18" woofer in a front-loaded, vented enclosure. The VRX918S was designed specifically for use in arrays with the VRX932LA Line Array speaker and VRX-AF Array Frame. In addition it may also be used in arrays consisting entirely of VRX918S subwoofers. The system offers complete input connection flexibility for compatibility with a variety of cabling schemes. A recessed, external switch allows selection of either contacts +1/-1 or +2/-2. Equally at home in ground stacked applications, the VRX918S is equipped with a top-mounted, threaded, 20 mm socket that can receive the optional SS4-BK pole. This adjustable height pole can be used to mount speakers equipped with standard 35 mm pole sockets and weighing up to 50 kg (100lb). The threaded socket minimizes buzzing and rattling and assures that the pole will be secure and straight. The enclosure is constructed of top quality birch plywood, coated in JBL's rugged DuraFlex finish and is heavily braced to maximize low frequency performance. The attractive CNC-machined, 16-gauge steel grille is internally lined with acoustically transparent foam to provide additional driver protection and give a very professional appearance. The rear of the enclosure is fitted with T-nuts which may be used to attach the optional WK-4 caster kit.