Section 7: Specifications; Performance - Orban OPTIMOD 5750 Operating Manual

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Orban 5750 Technical Manual Specifications

Section 7: Specifications

It is impossible to characterize the listening quality of even the simplest limiter or compressor based on
specifications, because such specifications cannot adequately describe the crucial dynamic processes that occur
under program conditions. There- fore, the only way to evaluate the sound of an audio processor meaningfully is by
subjective listening tests.
Certain specifications are presented here to assure the engineer that they are reasonable, to help plan the
installation, and make certain comparisons with other processing equipment.

Performance

Except as noted in the text, specifications apply for measurements from analog left/right input to stereo composite
output and to FM analog left/right output.
Frequency Response (Bypass Mode): Follows standard 50μs or 75μs pre-emphasis curve ±0.10 dB, 2.0 Hz–15 kHz.
Analog left/right output and digital output can be user- configured for flat or pre-emphasized output.
Noise: Output noise floor will depend upon how much gain the processor is set for (Limit Drive, AGC Drive, Two-
Band Drive, and/or Multi-Band Drive), gating level, equalization, noise reduction, etc. The dynamic range of the A/D
Converter, which has a specified overload-to–noise ratio of 110 dB, primarily governs it. The dynamic range of the
digital signal processing is 144 dB.
Total System Distortion (de-emphasized, 100% modulation): <0.01% THD, 20 Hz–1 kHz, rising to <0.05% at 15 kHz.
<0.02% SMPTE IM Distortion.
Total System L/R Channel Separation: >50 dB, 20 Hz – 15 kHz; 60 dB typical.
Polarity (Two-Band and Bypass Modes): Absolute polarity maintained. Positive-going signal on input will result in
positive-going signal on output when HD Polarity and FM polarity controls are set to POSITIVE.
Processing Sample Rate: The 5750 is a "multirate" system, using internal rates from 64 kHz to 512 kHz as appropriate
for the processing being performed. Audio clippers operate at 256 kHz (and are anti-aliased), while the composite
limiter operates at 512 kHz.
Peak Control at HD Output: The peak limiter is oversampled at 256 kHz, yielding a worst- case overshoot of 0.5 dB
at the analog output and for all output sample rates. (To achieve this performance at 32 kHz output sample rate, it
is necessary to set the 5700i's HD lowpass filter cutoff frequency to 15 kHz.)
Processing Resolution: Internal processing has 24 bit (fixed point) or higher resolution.