Section 4: Architect’s and Engineer’s Specifications

The Digital Signal Processor (DSP) shall provide two independent channels of DSP for signal delivery to QSC DataPort equipped power amplifiers. The processing shall be distributed with the DSP module mounted directly to the rear of the power amplifiers.

Output Peak Limiter—For each audio channel, the DSP shall provide a peak limiter that is assignable anywhere in the signal chain and can be switched on or off. The limiter shall provide the following adjustments:

Gain

Threshold

Attack time

Release time

High- and Low-Pass Crossovers—For each channel of audio, the DSP will provide high-pass and low-pass crossovers that are assignable anywhere in the audio chain. The crossovers must be capable of being switched in or out of the signal chain. The DSP shall provide the following crossover responses:

Butterworth (6,12,18,24 dB per octave slope)

Bessel (6,12,18,24 dB per octave slope)

Linkwitz-Riley (12 & 24 dB per octave slope)

High- and Low-Pass Shelf Filters—For each audio channel, the DSP shall provide high-pass and low-pass shelf filters that are assignable anywhere in the audio chain. The shelf filters must be capable of being switched in or out of the signal chain. The DSP shall provide the following shelf filter adjustments:

Variable corner frequency

Variable gain

Variable slope

Compressor--The DSP shall provide a signal compressor that is assignable anywhere in the signal chain. It shall have adjustable threshold, attack time, release time, and compression ratio.

Contact Closure I/O—The DSP shall provide a trigger input usable for contact-closure (or other) purpose which shall be CMOS & TTL signal compatible.

Power Supply—The DSP shall be provided power through its DataPort connection to QSC amplifiers. For older ampli- fiers or non-QSC amplifiers, a coaxial power jack will be provided on the DSP for connection to an external power source. Power required shall be +15 VDC at 300 mA (max.).

Amplifier Interface—The DSP shall attach directly to the rear of each power amplifier. The DSP’s interface to each power amplifier Data Port shall be via an HD-15 connector. This interface shall transmit two amplifier input audio signals as well as all control and monitoring signals. Special signal conditioning and grounding techniques shall be used in this interface to ensure negligible levels of noise and crosstalk. For non-DataPort amplifiers, there shall be mounting and interface options provided for operating with the DSP.

Amplifier Output Monitoring—When used with QSC DataPort amplifiers, the DSP shall provide clipping and protect status detection at the amplifier’s output terminals.

Noise & Tone Generation-- The DSP shall provide pink and white noise generation capability. It shall also provide for tone generation.

Presets— The DSP shall be capable of storing at least 8 preset configurations. The control software shall provide man- agement of these presets.

General—All audio inputs and outputs shall be balanced with a nominal input level of +4 dBu and maximum level of +21 dBu. Input connectors shall be of the “Phoenix” detach- able terminal block type.

Control— The DSP shall be configurable via RS-232 or via a networked DataPort connection.

The Digital Signal Processor shall be the QSC DSP-3.

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QSC Audio DSP-3 manual Architect’s and Engineer’s Specifications, Gain Threshold Attack time Release time

DSP-3 specifications

QSC Audio has long been recognized for its commitment to delivering high-quality audio solutions, and the QSC DSP-3 is no exception. This advanced digital signal processor (DSP) embodies cutting-edge technologies, designed to enhance audio systems in a variety of environments, including live sound, broadcasting, and installation applications.

One of the main features of the DSP-3 is its exceptional audio processing capabilities, boasting 32-bit floating-point processing for superior sound quality. This ensures that audio remains clear and dynamic, with minimal distortion, even under demanding conditions. With a frequency response of 20 Hz to 20 kHz, the DSP-3 caters to a wide range of audio frequencies, ensuring no detail is lost in the sound.

The DSP-3 offers extensive input and output options, including multiple analog and digital inputs and outputs. This flexibility allows for seamless integration into existing sound systems, catering to various setups while accommodating different signal formats. Users benefit from the unit’s configurability, enabling tailored solutions for different applications.

One of the standout technologies integrated into the DSP-3 is its advanced FIR (Finite Impulse Response) filtering capabilities. FIR filters are known for their phase linearity, which is crucial for maintaining the integrity of the audio signal through the processing chain. This feature helps in achieving accurate sound reproduction, ensuring a natural listening experience.

Additionally, the DSP-3 comes equipped with a user-friendly interface, featuring real-time monitoring and control options. This interface allows sound engineers and technicians to swiftly make adjustments on the fly, resulting in optimized audio performance tailored to the specific venue or event.

Another notable characteristic of the DSP-3 is its robust protection features. With built-in limiters, compressors, and equalizers, the device safeguards audio equipment from damage due to excessive signal levels, while maintaining the best audio quality possible. This added layer of protection is invaluable in live sound scenarios, where unpredictable dynamics can occur.

Overall, the QSC DSP-3 stands out as a powerful and flexible digital signal processor that meets the needs of modern audio applications. Its combination of advanced processing capabilities, extensive connectivity, intuitive interface, and protection mechanisms makes it an essential tool for audio professionals aiming to achieve exceptional sound quality in diverse environments. Whether for live events, installations, or broadcast applications, the DSP-3 enhances audio performance and reliability, solidifying QSC's reputation as a leader in the audio industry.