OSD Black BK-TreVoce12 is a dynamically powered subwoofer that offers up to 800 Watts of power and a three-woofer design that dramatically enhances bass in home theaters, media rooms, and high-end listening spaces. This robust stand-alone subwoofer has a unique configuration that includes a 12” active woofer and two 12” symmetrically built passive woofers. The active subwoofer is self-contained and uses the sub’s amplifier to reproduce sound while the two passive symmetrically built woofers enhance the SPL, all contained within its small enclosure. This delicate balance of internal and external power relieves your main speakers from having to produce too much low-frequency sound, allowing them to focus on mid-range and highs. The result is optimal performance, so you’ll experience movie and music soundtracks with prodigious, and tightly controlled, bass authority.