The 18" JBL PRX718XLF 1500W Extended Low Frequency Self-Powered Subwoofer is designed for sub bass sound reinforcement such as for concerts, DJs, and houses of worship, among others. The subwoofer is built from poplar plywood with an obsidian DuraFlex finish using tongue and groove joinery for stronger bracing and less box vibration. It utilizes an 18" 2278G low-distortion, low-frequency dual voice-coil and magnetic gap woofer and a 1500W class-D amplifier to achieve a peak SPL of 134 dB and a frequency response of 30 to 103 Hz.
For easy transport and setup, the subwoofer includes two injection molded handles, 16-guage steel dent resistant cloth backed grills, and an integrated speaker pole socket for SS4-BK or SS4-BK24 speaker poles.
The back panel of the speaker features two combination 3-pin XLR and 1/4" balanced inputs and a High Pass/Full Range pass-thru button. A gain control knob allow you to adjust the input signal on channels 1 and 2, and a pair of 3-pin XLR male thru connections enable passing audio to another subwoofer, powered speaker, or amplifier. The device includes a polarity button for inverting the subwoofer's phase and a button for turning on and off the power/standby LED on the front of the unit.
The speaker's crossover, dynamic limiting, component optimization, and selectable EQ boost is handled by a dbx type IV circuit. The subwoofer can be used by itself to reinforce the low end of a PA speaker system or in multiple subwoofer setups for increased crowd coverage.