Gravis II uses a down-firing 10-inch driver and a front-firing 10-inch passive radiator. A 400-watt Class AB amplifier gives it enough control and output for medium-size rooms without the bulk of the Reference-level models.
Line, LFE, and high-level inputs let it join either a stereo or theater system. Its strongest role is extending floorstanders or larger monitors with low bass that stays full and controlled rather than drawing attention to the subwoofer.