RCF S 15 Bass Reflex Subwoofer - 15"S 15 is a high power, compact subwoofer system ideal for installations where the physically small size and impact of a 15'' driver are desired. Extending the frequency response below 35Hz, this highly efficient design is capable of providing output levels normally associated with considerably larger enclosures. A system suited to music playback in applications ranging from clubs, bars and cafes, right through to theatres and corporate applications.