Audio professionals looking for a powered subwoofer that complements the SONAR Xi full-range speakers will be impressed with the HK Audio SONAR 115 Sub D, a compact, active subwoofer with a 1500W peak amplifier that powers the 15" woofer that produces frequencies as low as 40 Hz with a maximum SPL of 128 dB. The SONAR 115 Sub D deliver high-quality sound and a whole catalogue of professional features at an affordable price point.