Speaker driver that handles the low frequency signals of a sound wave. Woofers may refer to large subwoofer drivers that handle the lowest bass signals or slightly smaller bass drivers that handle bass signals but not necessarily the lowest octave (from around 40 Hz down). oofers designed for bass use, but not ultra-low bass, tend to range in size from around 6 inches (diameter) to 8 inches. Those designed to operate lower into the frequency spectrum are usually 10 inches or larger (up to 18 inches for large subwoofers playing below 20 Hz). In most cases, woofers reproduce frequencies below around 400 Hz to 500 Hz with low-bass specific woofers playing below 80 Hz or so. In most cases, a midrange driver then takes over above 400 Hz or so up to around 2,000 Hz where the tweeter takes over the high frequency tasks. These estimates, however, are very general and change depending on the specific drivers used, the speaker configuration, etc.