The PRX418S is a compact, high power subwoofer system containing a JBL Selenium 457mm (18") woofer in a front-loaded, vented enclosure. The enclosure is designed to present a minimum frontal area. The system offers complete input connection flexibility for compatibility with a variety of cabling schemes. The input panel incorporates a pair of Neutrik Speakon NL-2 / 1/4" TS phone combo jack connectors wired in parallel. The PRX418S is supplied with pins +1/-1 connected to the woofer. The enclosure is constructed of birch/poplar multi-laminate hardwood and coated in JBL's rugged DuraFlex finish. The distinctive 16-gauge steel grille is CNC-machined for precision. The grilles are internally lined with an acoustically transparent screen to provide additional driver protection and give a very professional appearance.