QSC Audio DSP-30 Architect’s and Engineer’s Specification, Bessel 6,12,18,24 dB per octave slope

Architect’s and Engineer’s Specification

The Digital Signal Processor (DSP) shall provide two independent channels of DSP for signal delivery to all professional power amplifiers. Input and output sensitivity shall be adjustable to accommodate consumer and pro audio signal levels.

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 bypassed. Its operation shall be based upon the peak signal level. The limiter shall provide the following adjustments:

Gain

Threshold

Attack time

Release time

Predictive Delay

High- and Low-PassFilters—For each channel of audio, the DSP will provide high-pass and low-pass filters that are assignable anywhere in the audio 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 bypassed. The DSP shall provide the following shelf filter adjustments:

Variable corner frequency

Variable gain

Variable slope

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.

Compressor--The DSP shall provide a signal compressor that is assignable anywhere in the signal chain. It shall be based upon the RMS signal level. The compressor shall be capable of being bypassed. The compressor shall provide the following adjustments:

Gain

Threshold

Attack time

Release time

Compression ratio

Predictive Delay

Power Supply—The DSP shall be provided power from an inter- nal power supply that operates from line voltages in the range of 100-240 VAC and frequencies from 40 to 63 Hertz. Line cord connection to the DSP shall be via an IEC- type line cord receptacle.

Amplifier Interface—The DSP shall connect to amplifiers using standard 3-pin XLR connections. Provisions for both bal- anced and unbalanced connection shall be provided.

Noise & Tone Generation--The DSP shall provide pink and white noise generation capability. It shall also provide for user-specified tone generation. Level control of noise and tone objects shall be provided

Presets— The DSP shall be capable of storing eight preset configurations. Preset recall capability shall be via two front panel push-button switches and shall not require the use of a computer. The control software shall provide management of these presets.

General—All audio inputs and outputs shall be balanced. Audio input and output sensitivity shall be programmable using the control software. Units will be user-selectable from dBu, dBV and Volts (rms).

Control— The DSP shall be configurable via a front panel acces- sible RS-232 port.

The Digital Signal Processor shall be the QSC DSP-30.

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