The VHD4.18 is a quad 18”subwoofer system comprising of four individual loudspeaker cabinets. When assembled, the VHD4.18 system becomes a high efficiency neodymium subwoofer system with immense output.Very high sensitivity 110dB (1W/1m) and a tremendous max. output of 149dB. Each cabinet incorporates a large port area that becomes an optimized horn aperture when all four cabinets are assembled. The quad 18” subwoofer system delivers extreme output, controlled low frequencies and resolution. Integrated Fly-Tracks, easy to transport and setup.