Wheatstone Corporation WheatNet-IP BLADE3, Техническое руководство, Страница: 207 / 366

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A U R A 1 I P P R O G U I
WheatNet-IP BLADE 3 / Jan 2016
Threshold
The first adjustment in each column is the Threshold (Thresh) control.
This control sets the level at which the AGC will start working (or processing)
the audio. If the AGC is defeated, then this control will govern the behavior
of the compressor.
Like many other controls, the Threshold control is calibrated in dFBS.
And, like the Gate Threshold discussed previously, the Threshold control
operates with a peak program reference level of -20dBFS. What this means is
that if the onset of AGC gain control action should begin 20dB below average
program level (to achieve 20dB of average compression), this control should
be set 20dB below the internal reference level, or at -40dBFS.
AGC Attack/Release
The next two adjustments in the column control the speed of the AGC.
The AGC Attack setting controls how fast the AGC adapts to increases in
audio levels. The range of the AGC Attack control is 50-500ms.
Conversely, the AGC Release control setting controls how fast the AGC
responds to decreases in audio level. The range of the Release control is
1000-7000ms (1 second to 7 seconds).
Recommending “perfect” settings for the AGC Attack and Release con -
trols is difficult because of how highly subjective the resulting processing will be. What
this means is that the settings are highly dependent on many factors including the desired
density of processing and its audibility. In general, slower settings in both controls create less
noticeable AGC action while faster settings cause the audibility of processing to increase.
If we were to recommend starting points for the AGC Attack and Release we would
specify around 300 ms for Attack and 4000ms (4 seconds) for Release. While the range
of the AGC Attack controls could achieve a 50ms Attack and 1000ms Release, we do not
suggest using AGC Attack times faster than about 150ms and Release times faster than
about 2000ms IF all parts of the processor are enabled (AGC, Compressor, Limiter, etc.).
Compressor Attack/Release
These next two adjustments control the timing of the Compressor. Unlike the AGC
however, the Compressor is designed to work primarily on short term dynamics and therefore
helps to not only build density, but it allows the limiters upstream to not work so hard on
the audio coming out of the AGC/Compressor stage.
The Compressor Attack (Comp. Attack) control range is adjustable between 3ms
and 100ms. Compressor Release (Comp. Release) is adjustable between 50 and 1000ms
(1 second). The ranges of the Compressor controls have been limited to what we feel are
the most useful settings and they cannot be set to sound bad. That said, we recommend
Compressor Attack settings of between 3ms and 20ms and Compressor Release settings
around 300ms. These settings may need to be modified to work better in concert with other
controls later downstream.