The BOSE's ROOMMATCH RMS215 subwoofer module was created to extend Bose RoomMatch® arrays' low-frequency response to 40 Hz. Dual Bose LF15 15-inch high-excursion woofers are used in the RMS215 subwoofer module, which has a patented port design that reduces distortion and improves perceived transient impact. The ground-stack enclosure of this passive speaker is made of sturdy Baltic birch with a two-part polyurethane coating.