DAS ACTION-S18A - Active 18-Inch Subwoofer (Black)ACTION S18A is a high power active subwoofer system that incorporates a 1500 Wpeak amplifier and single 18FW4 speaker with a 3 coil and 20 mm winding depth, double layer and sandwich to boost system power, as well as a new forced convection circuit that that works to reduce the effects of voice coil heating. As part of a company culture, all DAS systems are developed under a single philosophy: to deliver the highest possible quality in terms of both