subwoofer

A subwoofer refers to either a driver, or a complete amplifier dedicated to the reproduction of bass audio frequencies, typically from 150 Hz down to 20 Hz. In the case of a rotary woofer, it is possible to reproduce frequencies down to 1 Hz. Bass frequencies below about 80Hz become increasingly difficult for typical floor standing or bookshelf loudspeakers to reproduce at high playback levels because they do not have large enough drivers to generate the required amount of air displacement. Therefore, subwoofers are useful for augmenting main loudspeakers by providing playback of low bass frequencies at high levels.