VELODYNE ACOUSTICS CHT-12BV Classic Home Theater Series Powered Subwoofer (Discontinued by Manufacturer) Integrates seamlessly with your system's electronics, from Dolby Digital ( AC-3 ) to DTS, THS, DSS, SACD and DVD-Audio! Fixed 85Hz high-pass crossover and variable low-pass crossover Anti-clipping and over-excursion protection 12-inch Forward Firing Subwoofer Frequency Response - 25-120 Hz +- 3dB