Subwoofer - Wikipedia, the free encyclopedia - A subwoofer (or simply "sub") is a woofer, or a complete loudspeaker typically between 8" and 21" in diameter, which is dedicated to the reproduction of low-pitched audio frequencies ... How to set up a subwoofer - Speakers & Headphones - Take our easy-to-follow procedures to integrate your powered subwoofer into a component-level home theatre system.