The B1-SUB is an actively driven subwoofer which uses a pair of 15 inch LF drivers mounted in a bass-reflex cabinet. The B1-SUB cabinet is constructed from marine plywood and has an impact resistant paint finish. The front of the loudspeaker cabinet is fitted with a rigid metal grill covered with a replaceable acoustically transparent foam, and fitted with catches to the top and bottom for securing an optional transport lid E7909. The cabinet incorporates four recessed handles, MAN CF4 stud plate rigging points and on the rear panel are ratchet strap guide plates (kelping bars) and four heavy duty wheels.