The JBL PRX818XLF is a self-powered extended low-frequency subwoofer system designed and engineered to provide sub bass frequencies with accuracy and power. Featuring a JBL 18-inch woofer powered by a 1500-watt class-D amplifier, PRX818XLF delivers incredible output in a lightweight and compact form factor. Used as a single sub in a sub/ sat system or in multiples as part of a scalable, large format sound reinforcement system, the PRX815XLF performs with exceptional efficiency and control. The subs are stackable and light-weight, ensuring quick set-ups and tear-downs. With the integrated stereo pass-thru this is the most powerful low-frequency complement to the PRX full-range systems. The addition of a polarity reverse option further enables system optimization. PRX800 subwoofers feature a standard M20 threaded pole cup that can accept most modern subwoofer-mounted speaker poles. The PRX800 series integrates embedded ioSYS technology which enables easier setup and control when used with the HARMAN Connected PA app and compatible products. Connected PA delivers seamless plug-and-play operation with a variety of HARMAN equipment and enables you to control your entire live sound system with one app. Products within the Connected PA system self-identify and retain presets for effortless setup, and setup wizards help you quickly optimize speaker levels, configuration settings and EQ. Current products with embedded ioSYS technology and HARMAN Connected PA compatibility include the Ui24R mixer, JBL PRX800 loudspeakers, dbx Di1 direct boxes, and AKG P5i microphones and the MDAi dynamic microphone adapter.