The 21S-SUB is a high performance subwoofer for use with the xS-Series and xA-Series loudspeakers and is intended for a wide range of permanently installed applications. The cabinet houses a single long excursion 21″ driver in a bass-reflex design. The large, specially shaped reflex port enables the 21S-SUB to achieve high Sound Pressure Levels from a cabinet with a small footprint. When operated in INFRA mode, the 21S-SUB can be used to complement other d&b subwoofers by extending the frequency response of the system down to 33Hz. The 21S-SUB can be ground stacked or flown in either orientation. It can be flown individually or in a cluster of two cabinets. The enclosure is constructed from marine plywood with an impact resistant black paint finish. The front of the loudspeaker cabinet is protected by a rigid metal grill backed by an acoustically transparent foam. The top, bottom and rear panels each incorporate a pair of M10 threaded inserts for attaching d&b rigging hardware. The Weather Resistant (WR) option provides an IP55 rating that enables the operation of loudspeakers in changing ambient conditions, and features a fixed cable.
The d&b 30D amplifier is recommended to drive the 21S-SUB. The d&b D20 and D80 can also be used.
Architectural specifications for detailed project planning
Do you require architectural specifications? For a d&b system or a specific d&b Series? Here are the most important technical specifications ready for download.