Korpa 
The JBL PRX518S offers the performance of an 18" sub-woofer in a package not much larger than a typical 15" sub. With a 36mm pole receptacle that accepts the JBL SS3-BK speaker stand on the top panel and integrated stereo pass-thru, with selectable HP filter, this is the perfect complement to the PRX500 full-range systems. Configured with a PRX512M or PRX515; the result is a highly transportable, high performance sub-satellite system. The addition of a polarity reverse option further enables system optimization.
The PRX518 is a high performance self-powered compact sub-woofer system. The PRX518S is comprised of a 2044E 460 mm (18") VGC (Vented Gap Cooled) woofer driven by a Crown International Class-D digital power amplifier. A propriety digital processing chip (DSP) chip is at the core of a fully featured input section, providing user selectable crossover functionality, polarity optimization, protection, dynamic limiting and discrete component optimization.
The enclosure is constructed of quality plywood and coated in JBL's rugged DuraFlex finish. An integrated pole mount on the top enables an easy sub/satellite configuration. The CNC machined steel grille wraps around the sides of the enclosure so there are no protruding lips on the front of the box to create acoustical interference. The grille is also lined with an acoustically transparent foam to provide additional driver protection.
The amplifier input panel offers stereo inputs with XLR or 1/4 inch jack compatibility. A user selectable crossover ensures a smooth transition to full-range system connected to the stereo outputs. Signal present and overload lights indicate the system status and assist in setting the optimum level, via the level control knob.
