Active Subwoofer 500W RMS @ 4 ohm Class D amplifier with switch-mode power supply, comprehensive protection circuitry and clip free limiting 40 – 200Hz Left & Right balanced Jack/XLR Combi inputs with full range (link) & Hi-pass filtered XLR outputs Variable low pass filter & phase reversal switch plus Master Volume with clip, power & protect LED's Rectilinear Sub cabinet with internal bracing. 18mm composite wood construction