For Immediate Press Release
For Additional Information, please contact:
Francois Godfrey,
Director of Sales, Cinema Division
QSC Audio
tel: 714-957-7133

Press Contacts:
Christopher Buttner
Tel: 415-233-7350
Europe: Jerry Gilbert
Tel: +44 (0)1707 258525

To Download the
"DCS SB-15121 Cinema Sub"
Press Release as a WORD Doc,
please click on this link.

QSC’s New 21-Inch LF Transducer Designed For Ultimate Performance In Premiere Cinema And Post-Production Applications

Click on image below to englarge or download high-res version for print publication.
DCS SB-15121 High-Output Cinema Subwoofer

October 13, 2009 - COSTA MESA, CA - Joining QSC Audio’s DCS Digital Cinema Speaker family, the new SB-15121 subwoofer offers the highest performance available in a dedicated cinema subwoofer enclosure. It has been designed for use in premiere cinemas and post-production applications where the ultimate in performance is required. 

The massive 1500W, 21-inch low-frequency transducer features a 6-inch diameter voice coil in a vented, neodymium magnet structure that is designed to dissipate extreme amounts of heat and allow for excursion that is double that of typical 18-inch transducers. This ensures cool operation, even at high power levels, increases driver lifespan and decreases power compression at high drive levels. 

The large, ported enclosure ensures response to the lowest audible frequency for bass cannot only be heard but also feel. In fact the frequency range extends to below 25Hz without the need for B6 EQ filters.

States Barry Ferrell, QSC senior director, Cinema Solutions, “The SB-15121 is a unique product with no direct competitive equivalent. It was designed with the most advanced measurement tools available to produce a rugged and nearly unbreakable transducer that is also capable of incredibly low distortion. Strength and finesse are combined in a truly state of the art component.

“As a result, premium cinemas can offer increased subwoofer performance to go along with enhanced seating and upscale concession items — and achieve a distinctive level of performance compared to their competitors.”

The enclosure is constructed of high quality, heavily braced MDF panels, while large, fully radiused ports ensure smooth airflow, especially at higher drive levels — thus preventing potentially audible port turbulence noise. Both internal and external port openings are flared. 

With symmetrical port loading, the bass ports are evenly spaced around the transducer, making internal pressure more uniform across the back surface of the woofer. This prevents the cone from being displaced to one side or another by unbalanced air pressure, reducing the chance of driving the voice coil out of the centre of the gap at high drive levels.

Also optionally available with the system are QSC’s DCP, DCM and SF-3 signal processors.

QSC Audio Products, Inc. is a leading manufacturer of power amplifiers, loudspeakers, signal processing, digital signal transport, and computer control systems for professional audio markets worldwide. For more information, contact QSC Audio Products, Inc., 1675 MacArthur Blvd., Costa Mesa, CA 92626 USA. Phone: 800-854-4079 (USA only) or 714-754-6175. Fax: 714-754-6174. E-mail:, or visit

Product specs are also online with high-res product image:

For additional information, please contact Francois Godfrey, contact info above.


For more info, please contact Christopher Buttner, contact info above.