Round out your home theater system with the high-performance Yamaha YST-SW225 120-watt subwoofer. Boasting an 8-inch multi-range driver and Yamahas QD-Bass and Advanced YST II technologies, the subwoofer adds a deep, powerful bass response to your favorite movies and music. QD-Bass technology employs down-firing drivers and square, pyramid-shaped reflective plates to radiate the sound efficiently in four horizontal directions, ensuring dynamic power and a smooth frequency response regardless of the subwoofers location. Advanced YST II technology, meanwhile, optimizes the speaker impedance to create more stable, energetic, and accurate low-range tones. Adding to the audio quality is the luxurious magnetically shielded wood-finished cabinet, along with the highly efficient internal amplifier that consumes little power while still producing a big sound. As a result, the speaker creates a clear, spacious sound stage that evokes the high-end audio at commercial movie theaters. The YST-SW225 produces a generous overall frequency response of 28 to 200 Hz, which dovetails nicely with the specs of Yamahas complementary 225 PMD home theater speaker series, which includes floor-standing tower models, rear bookshelf units, and a center channel speaker. Additional features include a linear port that minimizes extraneous noise and distortion, a Bass Action Selector System (BASS) that lets you switch between movie and music modes to enjoy an optimum frequency response for each, and a low-power standby mode that consumes only 0.5 watts of power. The subwoofer measures 11.44 by 13.88 by 13.75 (W x H x D) and carries a two-year warranty on parts and labor.