User manual QSC AUDIO SB-15121

[. . . ] Install in accordance with QSC Audio Product's instructions and a licensed, professional engineer. Only use attachments, mounts, accessories, or brackets specified by QSC Audio Products, LLC. Refer all servicing to qualified personnel. Servicing is required when the apparatus has been damaged in any way. Warranty (USA only; other countries, see your dealer or distributor) Disclaimer QSC Audio Products, LLC is not liable for any damage to amplifiers or any other equipment that is caused by negligence or improper installation and/ or use of this loudspeaker product. QSC Audio Products 3-Year Limited Warranty QSC Audio Products, LLC ("QSC") guarantees its products to be free from defective material and/or workmanship and will replace defective parts and repair malfunctioning products under this warranty when the defect occurs under normal installation and use-provided the unit is returned to our factory, one of our authorized service stations or an authorized QSC International Distributor via pre-paid transportation with a copy of proof of purchase (i. e. , sales receipt). [. . . ] The QSC limited warranty is valid for a period of three (3) years from date of purchase in the United States and many (but not all) other countries. For QSC warranty information in countries other than the United States, contact your authorized QSC international distributor. A list of QSC International distributors is available at www. qscaudio. com. To register your QSC product online, go to www. qscaudio. com and select "Product Registration". Other questions regarding this warranty can be answered by calling, e-mailing or contacting your authorized QSC distributor. QSC is a registered trademark of QSC Audio Products, LLC. "QSC" and the QSC logo are registered with the U. S. All trademarks are the property of their respective owners. 1 Introduction Part of the DCS Digital Cinema Speaker Series, QSC's SB-15121 subwoofer offers the highest performance available for cinema subwoofer applications. It is designed for use in premiere cinemas and post-production applications where the ultimate in performance is required. The massive 21" low-frequency transducer features a 6" 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" transducers. Ensuring 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 that you can not only hear but also feel. The enclosure is constructed of high quality, heavily braced MDF Panels. Large, fully radiused ports ensure smooth airflow, especially at higher drive levels. This prevents 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 center of the gap at high drive levels. [. . . ] Four terminals: (two INPUT and two PARALLEL OUT). Vented enclosure with symmetrical port design, tuned to 25 Hz, constructed of medium density fibreboard and heavily braced. Features vandal resistant woofer mounting bolts. 48. 8" x 30" x 24" (1238 mm x 762 mm x 610 mm) including feet 257 lb / 114 kg 231 lb / 105 kg 137 dB SPL 1 meter, half space, at rated rms power with 6 dB crest factor pink noise input, 40 Hz ­ 100 Hz 131 dB SPL 1 meter, half space, at rated rms power with 6 dB crest factor pink noise input, 40 Hz ­ 100 Hz 4 nominal 23. 8 Hz ­ 250 Hz 21. 5 Hz ­ 250 Hz Recommended Processing Nominal Coverage Connectors Enclosure Dimensions (HWD) Weight Shipping Net Weight 4 SPL and Impedance vs. [. . . ]