The PreSonus Air18S active PA subwoofer exhibits a powerful, clear, and accurate low-end punch that belies its compact, lightweight form factor. An 18" woofer is powered by 1,200 watts delivered by a super-efficient Class D amplifier. A variable lowpass filter dials in your upper frequency limit from sub-bass to full-range, while DSP presets enable extended low-end performance, so creating ground-stacked or endfire subwoofer arrays is childs play. Great for both mobile use and permanent installations, the PreSonus Air18S active PA subwoofer is the perfect complement to your full-range Air10, Air12, or Air18 PA system. PreSonus Air18S Active PA Subwoofer Features at a Glance: 1,200W Active PA Subwoofer with 18" LF Driver Onboard mixer with 2 XLR/TRS combo inputs and stereo 1/8" input Variable lowpass filter dials in your upper frequency limit from sub-bass to full-range Convenient DSP presets enable extended low end for ground-stacked or endfire subwoofer arrays Up to