The 18" 500W professional active PA subwoofer with built-in stereo crossover. EUROLIVE VQ1800D 500W active subwoofer provides the ultimate in low-frequency reproduction and the built-in stereo crossover makes it ideally suited for use with any of our active 2-way loudspeakers. Packed with a powerful 500W class-D amplifier, 18" long-excursion low-frequency (LF) transducer and an incredible array of professional features, the VQ1800D produces extreme levels of low-end punch, with the definition and clarity typically reserved for much larger systems. Put simply, these cool-running systems are much lighter, making them ultra-easy to transport and set up and our no-compromise design means you get amazingly-deep, chest-pounding bass that will keep the party going all night long.