SW15For bass lovers, the subwoofer can never be too big. And for SW subs, we want to make sure our customers invest every penny in performance, and nothing else. A 15 inch sub is a common size for big rooms. We optimized our 15 inch driver for high efficiency. We don't like slow, muddy sound at all so we designed a fast response coil. With all of these elements, we have a fast and powerful, competitively priced 15 inch subwoofer.