The Bi6-SUB is a high performance subwoofer designed for ground stacked applications, housing a long excursion 18” driver built into a bass-reflex design. The Bi6-SUB is the installation version of the B6 subwoofer and differs only in cabinet construction, finish and mounting hardware. When three or any multiple of three Bi6-SUBs are used, they can be positioned in a Cardioid Subwoofer Array with one cabinet physically facing backwards and driven by an amplifier channel with CSA mode selected. This achieves exceptional directivity control in lower frequencies and significantly reduces the energy radiating towards to the rear. The cabinet is constructed from marine plywood and has an impact resistant paint finish, whilst Weather Resistant and Special Colour options are available. The front of the loudspeaker cabinet is protected by a rigid metal grill backed by an acoustically transparent foam.