dbx DriveRack 220i, User Manual

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20
220i
DriveRack
®
User Manual
Sensitivity -20-+20dB
The AFS algorithm is very effective when the audio has a nominal level of 0 dBu, however if the audio
is too low in level the AFS algorithm may not catch feedback as quickly as possible. By increasing or
decreasing the sensitivity you can adjust for audio that is either too loud or too soft and help the AFS
function properly.
3.4 - Automatic Gain Control (AGC)
The AGC is used to keep the average level of a signal at a constant level. This is done by selecting
a desired Target output level and Window. The AGC keeps the signal within the Window about the
selected Target by slowly adjusting the gain. The maximum gain that can be applied to the signal is
selected by the Gain parameter. When the input signal falls below the Low Threshold the AGC releases
the gain and returns to unity. This prevents the AGC from adding gain when there is no signal present
and raising the system noise floor. High level signals are reduced by a fast limiter to prevent distortion
by clipping. The AGC Threshold meters show what region of the AGC the input signal is in. The
T (yellow) indicates the signal is within the Window. A + (red) indicates the signal is going into the
Limiter. A – (green) indicates the AGC is adding Gain and is at or below the window. When the
Threshold meter is off the signal is below the Low Threshold.
AGC: On/Off
Turns the AGC module On and Off.
Target: -20 to 20 dB
The Target parameter defines where you would like the average level of the AGC output to be. If the
average level of the signal rises above the Target the gain will be reduced. For signals with an average
level below the Target the gain will be increased.
Gain: 1 to 20dB
This adjusts the maximum amount of gain that can be added by the AGC.
Window: 1 to 10dB
This adjusts the amount of variation in the output
Detailed Parameters
Section 3