A type of speaker enclosure used with subwoofers to produce large amounts of bass with minimal power input by utilizing essentially a sealed subwoofer enclosure mated to a ported box. A bandpass enclosure first uses a sealed subwoofer enclosure with an outward firing bass driver. This enclosure is sealed to a second enclosure with the bass driver firing into the second enclosure. The second enclosure does not have its own driver only a port. The audio output developed by the driver is reinforced in the second ported enclosure and then emerges through the port. In a bandpass enclosure the bass driver is not visible from outside the complete enclosure, and all the sound output comes through the port or tube. andpass enclosures maximize the output of a speaker driver over a narrow range of low frequencies. The enclosure must be carefully designed and built to strict tolerances in order to operate properly. Bandpass enclosures are typically not used for high-end, high-quality subwoofers. They are limited in the frequency band they can reproduce and their sound quality is generally inferior to well-designed traditional subwoofer enclosures using ported or sealed designs.