CHAPTER 10 |
46
AM MENU
Input AGC Menu
The
Input AGC
Menu is used to set the ratio, maximum gain, attack rate, release rate, target, gate threshold, and
freeze threshold.
The Input AGC is the first gain control stage in Omnia.7 following Undo and is designed to be used as a slower-act-
ing leveler ahead of the Wideband AGC1 and multiband compressor sections that follow it.
It is worth noting that traditional processors only act upon audio above a particular threshold. They are driven into
various amounts of gain reduction, but once the audio falls below the threshold, they “run out of room” or “top
out” and are incapable of increasing the audio any further. This necessitates some sort of make-up gain control later
in the audio chain.
The AGC’s in Omnia.7 operate both above AND below threshold (as you can see by observing the scale on the
Input AGC meter) thereby controlling the dynamics over a much wider range without the need for makeup gain.
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The
Ratio
control determines how much the output audio will be increased or decreased in relationship to
the input audio of the Input AGC section. For example, a ratio of 3:1 means that for every 3dB of change
in the level of the input audio, the output will be changed by 1dB. Lower (looser) settings provide less
control of the dynamics in this section but provide a more open sound, while higher (tighter) settings
provide more control at the expense of openness.
♦
The
Maximum Gain
control works in conjunction with the Ratio control to determine how much gain is
available below target. If the Input AGC Ratio is set at Infinity:1 and the Input AGC Maximum Gain is set
to 36dB, the Input AGC has 36dB of range below target. At a ratio of 2.0:1 and the same Maximum gain
setting, the range is reduced by half to 18dB. The scale to the left of the Input AGC meter automatically
adjusts as needed when changes are made to the Input AGC Maximum Gain or the Input AGC Ratio to
accurately reflect how much range is available below target.
♦
The
Attack
control determines the speed with which the Input AGC acts to reduce audio above target.
Lower settings represent slower attack speeds and allow more audio to pass unprocessed by the Input
AGC into subsequent processing stages. Higher settings result in faster attack speeds and allow less
unprocessed audio to enter subsequent sections.
