Subwoofers

A subwoofer or a sub is a loudspeaker dedicated to reproducing low-frequency audio or bass. The typical frequency range for a subwoofer is about 20 to 200 Hz and below 80 Hz in THX-approved systems. Subwoofers are often used to augment the low frequency range of loudspeakers covering higher frequency bands only, such as satellite loudspeakers. With satellite loudspeakers becomming more popular and their physical size ever decreasing subwoofers play an important role in giving home cinema systems their full range sound. Passive subwoofers have a subwoofer driver and enclosure and they are powered by an external amplifier. Active subwoofers are more common and include a built-in amplifier.