The Mackie SRM1850 is a 18" Powered Subwoofer is that is professionally designed for extending the low-frequencies of sound systems and it is very well suited for various sound reinforcement applications including houses of worship, portable DJ's, theater, live stage, rehearsals, and more. The integrated Class-D amplifier is capable of driving a 1600W of power to the 18" woofer, which is providing a frequency response of 40 to 120 Hz with a max SPL of 132 dB. The tour-grade poplar plywood enclosure is front ported and internally braced for delivering a maximum low-frequency extension and punch.