The black MB12 from Bose is a modular bass loudspeaker designed to provide bass augmentation for Bose LT arrays and other subwoofer applications. The Baltic birch enclosure features a single 12" high-excursion woofer with a 4" voice-coil and a power handling of 400W RMS (1600W peak). The subwoofer offers a frequency response of 40 to 280 Hz and features a front-loaded transmission line design that provides a peak-free extended low-frequency, reducing port turbulence distortion.