HK Audio PR:O 118 SUB D2, Active Bass Reflex Subwoofer, Speakers: 1x 18"", 1200 W Class D power amplifier, Max. SPL (sound pressure level): 127 dB, Frequency response (+/-3 dB): 45 Hz - 150 Hz, Active selectable crossover: 75 Hz - 150 Hz, 2 XLR/jack input/output, 2 XLR thru, M20 thread for a pole mount,