LF-3115Low Frequency Loudspeaker Introduction

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Cinema Loudspeaker Systems User Manual

LF-3115Low Frequency Loudspeaker

Introduction

The LF-3115 15” (381mm) low frequency enclosure is designed specifically for cinema appli- cations. Meeting cinema requirements for extended low frequency response differentiates the LF-3115 from more conventional “rock-and-roll” woofer systems. The LF-3115 covers the frequency range from 33 Hertz to 1900 Hertz, depending upon the high frequency system requirements.

The 300 watt, 15” transducer is well suited for cinema use. It features a 3” (76mm) voice coil, ceramic magnet, and a multi-vented pole piece to ensure cool operation. Cooler temper- atures increase transducer lifespan and decrease the problem of power compression at high power levels. The suspension and voice coil of the transducer have been designed to provide low distortion and high impact bass at high power.

The enclosure is constructed of high quality medium density fiberboard panels with stiffen- ing braces on all panels. Both internal and external port openings are fully radiused ensuring smooth air flow at higher power levels, preventing audible port turbulence. The stiffening braces reduce panel resonance.

Bass ports are evenly spaced on each side of the transducer, making internal pressure more uniform across the back surface of the transducer. This prevents the cone from being dis- placed to one side or another by unbalanced forces, reducing the chance of driving the voice coil out of the center of the gap at high power.

Three T-nuts in the top of the enclosure provide easy mounting of QSC high frequency sys- tems, such as the HF-63.

Enclosure is not designed to be suspended, flown, or rigged. Do not sus- pend, fly, or rig this enclosure.

This product is capable of producing sound pressure levels that can perma- nently damage human hearing. Always keep sound pressure levels in the listening area below levels that can damage human hearing.

Install in accordance with QSC Audio Product’s instructions and a licensed, professional engineer. Only use attachments, mounts, accesso- ries, or brackets specified by QSC Audio Products, Inc. Refer all servicing to qualified personnel. Servicing is required when the apparatus has been damaged in any way.

WARNING! Before placing, installing, rigging, or suspending any speaker product, inspect all hardware, suspension, cabinets, transducers, brackets and associated equipment for damage. Any missing, corroded, deformed or non-load rated component could significantly reduce the strength of the installation, placement, or array. Any such condition severely reduces the safety of the installation and should be immediately corrected. Use only hardware which is rated for the loading conditions of the installation and any possible short-term unexpected overloading. Never exceed the rating of the hardware or equipment. Consult a licensed, professional engineer when any doubt or questions arise regarding a physical equipment installa- tion.

Mounting points for

high frequency system

TD-000172-00

QSC® is a registered trademark of QSC Audio Products, Inc. “QSC” and the QSC logo are registered with the U.S. Patent and Trademark Office

SC-312X specifications

The QSC Audio SC-312X is an advanced two-way loudspeaker designed to meet the demands of various audio applications, from live sound reinforcement to installations in sports venues, auditoriums, and houses of worship. This versatile loudspeaker is known for its exceptional sound quality, durability, and user-friendly features that make it a popular choice among audio professionals.

One of the standout features of the SC-312X is its powerful coaxial design. Utilizing a 12-inch low-frequency driver and a 1.4-inch exit high-frequency driver integrated into a single point source, this configuration allows for a more uniform dispersion of sound across a wide listening area. This results in improved clarity and reduced phase cancellations, ensuring that the audio is consistent regardless of the listener's position in relation to the speaker.

The SC-312X incorporates QSC's advanced DMT (Directivity Matched Transition) technology, which is designed to provide a smooth frequency response across the entire coverage pattern. This technology enables the loudspeaker to maintain a consistent tonal balance both on and off-axis, making it ideal for applications where audience coverage is critical.

In terms of construction, the SC-312X is built to withstand the rigors of professional use. Its cabinet is made from rugged plywood, finished with a durable coating that helps protect against wear and tear. Additionally, the front grille is made from perforated steel, providing extra protection for the drivers while allowing for optimal sound output.

Another important characteristic of the SC-312X is its versatility in rigging and mounting options. The loudspeaker comes equipped with integral fly points, which simplifies the process of suspension in various configurations. It also features a stand-mountable design, making it suitable for both permanent installations and portable setups.

The speaker’s power handling capability is impressive, accommodating a wide range of amplifiers and making it suitable for large venue applications. The SC-312X delivers a powerful output without sacrificing audio fidelity, ensuring that every nuance of the performance is captured and conveyed to the audience.

In summary, the QSC Audio SC-312X is an exceptional loudspeaker that combines innovative technology with robust construction to deliver unparalleled performance in any professional audio setting. Its coaxial design, advanced DMT technology, rugged build quality, and flexible mounting options make it a reliable choice for audio engineers and sound professionals looking to achieve the highest standards in sound reproduction.