Architect's & Engineer's Specifications The loudspeaker shall be an ultra-compact passive subwoofer. Its transducers shall be two 6.5 inch (165 mm) low frequency drivers with 1.2 inch (30 mm) voice coil in a bass reflex enclosure. Performance specifications of a typical production unit shall be: Measured ensitivity SPL at 1 m (3.3ft) with 2.0V input, shall be 94 dB-SPL. Usable frequency response shall extend from 53 Hz to 200 Hz (10 dB below rated ensitivity, in full space, with no external equalization). Nominal impedance shall be 4 Ohms. Rated power capacity shall be at least 100 Watts continuous power and 400 Watts peak power, defined as 6 dB above a test signal of filtered random noise. The enclosure shall be constructed from prime-grade 15 mm plywood. The grilles shall be of heavy-duty steel. The loudspeaker shall be equipped with a total of three (3) suspension points and shall be fitted with a M20 threaded pole-mount plate on the top, and a handle on one side. The external wiring shall be via either two 4-pin twist-lock or one 4-pin Euroblock connectors. The loudspeaker shall be 9.45 inches (240 mm) high by 18.5 inches (470 mm) wide by 14.57 inches (370 mm) deep weighing 25.3 pounds (11.5 kg). The finish shall be a paintable lightly textured black or white. The ultra-compact subwoofer shall be the Crest Audio CPL 265B+ with included U-Bracket or approved equivalent.