Overview The 1400-watt dual 12-inch active PSA1S bass reflex subwoofer is the ideal companion sub for the PSA1 full range loudspeaker system. Solid 15mm birch plywood cabinet construction and an integrated all-metal pole-mount adaptor make the PSA1S the perfect platform for stacking PSA1 cabinets in a scalable array system. Compact design, heavy-duty wheels and handles ensure the PSA1S can easily be handled by a single operator for economical system set-up.