REL Acoustics Q108 MK II 100W Mosfet Sub-Bass Speaker System Subwoofer. New.....this sub sells for $750! Don't lowball me. An ultra-compact sub-bass system designed for use in stereo music or film sound systems where exceptional low frequency output and extension is desired. Housed in an sealed, cube-shaped enclosure incorporating REL’s unique Zero-Q loading system, the Q-108E achieves an impressive in-room response of 23Hz at –6dB!  Featuring a downward firing, long-throw 8” steel basket driver with a vented pole-piece coupled to a true 100W discrete, direct-coupled MOSFET power amplifier, the Q-108E delivers ample low frequency output that belies its small physical size. Designed for use singly or in pairs, the Q-108E is the perfect addition to your stereo, home theater or computer multimedia speaker system.