Built-in controls for variable volume, low pass filter and phase (0/180°) for optimum bass levels. Set power toggle to Auto on/off or DC control (12V trigger) for fast and easy on/off power switching in the sub and other home theater equipment-all easily accessible on the back panel. Strong, rigid and acoustically inert enclosure reduces unwanted internal standing waves for less audible coloration. And non-resonant Meddite MDF construction, with extra bracing and minimum thick baffles, ensures a more lifelike sound. Connect via LFE (unfiltered / low pass disabled) or stereo line level RCA inputs-complements any home theater system (cables not included)