The J-SUB is an actively driven 2-way bass-reflex design housing three long excursion neodymium 18" drivers, two drivers face to the front and one driver to the rear. The cardioid dispersion pattern resulting from this approach avoids unwanted energy behind the system, which greatly reduces the reverberant field at low frequencies and provides the greatest accuracy of low frequency reproduction. J-SUB cabinets can be used to supplement J8 and J12 loudspeakers in various combinations, ground stacked or flown, either integrated on top of a J8 / J12 array or as a separate column.

The J-SUB cabinet is constructed from marine plywood and has an impact and weather protected PCP (Polyurea Cabinet Protection) finish. The front and rear of the loudspeaker cabinet are protected by a rigid metal grill and the side panels incorporate eight handles. Four 100 mm wheels and one NL8 connector are mounted at the rear.