Agc (Automatic Gain Control) - Orban OPTIMOD 5750 Operating Manual

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Operation
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DEPTH – Controls the amount of L-R delay (available only in the DELAY option)

AGC (Automatic Gain Control)

The AGC is a two-band device, using Orban's patented "master / bass" band coupling. It has an additional important
feature: target-zone gating. If the input program material's level falls within a user-settable window (typically 3 dB),
then the release time slows to a user-determined level. It can be slow enough (0.5 dB/second) to effectively freeze
the operation of the AGC. This prevents the AGC from applying additional, audible gain control to material that is
already well controlled. It also lets you run the AGC with fast release times without adding excessive density to
material that is already dense.
The AGC contains a compression ratio control that allows you to vary to ratio between 2:1 and essentially 20:1.
Lower ratios can make gain riding subtler on critical formats like classical and jazz.
The AGC has its own silence-gating detector whose threshold can be set independently of the silence gating applied
to the multiband compressor.
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AGC ON/OFF – Lets you decide whether the AGC is operating in the signal chain or is bypassed. If you have a
leveler ahead of the 5750, it is best to turn off the AGC.
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AGC DRIVE – Sets the applied level to the AGC, determining the amount of overall gain reduction. This also
adjusts the "idle gain"—the amount of gain reduction in the AGC section when the structure is gated. (It gates
whenever the input level to the structure is below the threshold of gating.)
The total amount of gain reduction in the Five-Band structure is the sum of the gain reduction in the AGC and the
gain reduction in the multiband compressor.
The total system gain reduction determines how much the loudness of quiet passages will be increased (and,
therefore, how consistent overall loudness will be). It is determined by the setting of the AGC Drive control, by the
level at which the console VU meter or PPM is peaked, and by the setting of the MB Drive (compressor) control.
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AGC CROSSOVER – Selects between LINEAR, LINEAR WITH NO DELAY or ALLPASS.
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AGC MASTER ATTACK – Controls the rate of gain reduction in the master band. The faster the time (in seconds)
the faster the attack.
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AGC BASS ATTACK – Same as the MASTER ATTACK but applies to the bass band.
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AGC RELEASE – Controls the rate of gain increase in the master band. Settings with higher numbers will result
in faster recovery times.
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AGC BASS RELEASE – Same as AGC RELEASE but applies to the bass band.
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AGC BASS THRESHOLD – Determines the threshold of the operation of the bass band. Higher numbers will allow
the bass band to processor lower audio passages.