The YST-SW315 is designed to provide extremely high quality bass performance for the enjoyment of both music and movies. It uses two highly acclaimed technologies, Advanced YST and QD-Bass, to deliver deep and powerful bass with an amazing degree of clarity. A BASS (Bass Action Selector System) switch lets you choose between Music and Movie modes and you can also adjust the cutoff frequency of the high cut filter, giving you the best possible response with every sound source. Sophisticated and powerful, this subwoofer will make every system sound a great deal better.