Omnia-6ex Use and Operation Manual – V: 1.20
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Wideband AGC (WB)
Wideband AGC Submenu
This is the first processing section within the Omnia, so the controls in this section affect the overall signal, its
density, and hence affect every other processing section following it. The job of the Wideband AGC is to erase long-
term audio level fluctuations, while doing so in a very unobtrusive manner.
The AGC Drive control is calibrated between –12dB and +6dB, and adjusts the signal level into the Wideband
AGC. This control should be adjusted to net approximately 12dB of gain reduction with typical programming. Too
little gain reduction can defeat the “leveling” function of the Wideband AGC. Too much gain reduction has little
additional benefit. Nominal gain reduction values for the Wideband AGC are between 10 and 15dB.
The Attack and Release controls set the Wideband AGC time constants in relative terms using the numbers 0 - 7.
Lower numbers are slower time constants, while higher numbers are faster time constants. Because the time
constants are program-dependent, calibrating these controls in absolute time values (ms/dB) would be useless—
therefore we use relative numbers. Use a higher number if you want “faster” attack and release, and a lower number
for “slower” attack and release. A special algorithm within the Wideband AGC Attack time circuit prevents the loss
of Wideband AGC gain reduction when the Attack time control is operated at extremely slow values.
The Make-Up Gain control sets the amount of gain to be filled in during quieter, softer program passages. The range
is OFF to 7. This function is also program dependent, and it interacts somewhat with the main Attack and Release
time constants. As the attack/release times are modified, the system also scales the Make-Up Gain time constants.
Use less makeup gain for processing more faithful to the source material; use more makeup gain for greater loudness
and “density.”
The Gate Threshold control sets the level at which gating of the AGC occurs, “freezing” the gain during short
pauses. Correct adjustment of this control helps to minimize “pumping”, and the increase of background noise
during pauses in programming. The control range is OFF to 7.
There are two RTP (Return to Platform) parameters, RTP Speed and RTP Level, which determine what happens to
the AGC gain when the Gate Threshold is reached and audio is gated. With the RTP Level set to -5, -10 or -15 dB
of gain reduction, the gain will return to that pre-defined level when gated. How quickly the target gain reduction
