Dual 18'' Passive Subwoofer. High-power LF supplement to TX2152. Low-distortion port design. Two high-excursion EVS-18S woofers. Use with processor and dedicated amp channel. 103 dB sensitivity, 138 dB max SPL. Power handling: 1000 W continuous, 4000 W peak. Frequency Range (-10 dB): 40 - 1500kHz. Mount points (6) for optional wheel kit. Braced plywood/MDF enclosure. Black EVCoat finish.