Active subwoofer. BX151A is a very compact and incredibly performing self-powered subwoofer suitable for both indoor and outdoor use, concert halls, theatres, clubs, medium sized venues. Combines with any loudspeaker system, no matter what brand, model or kind. BX151A is equipped with a MosFet, class AB power amplifier, designed around an innovative driver stage that guarantees the lowest possible distortion, while providing excellent dynamic and tonal performance. The on-board power amplifier delivers a total output power of 500 watts. Dimensions: 500 x 580 x 470 mm. Weight: 38kg.