24
25
Utilities
Signal Meter
1
-
Signal Meter block indicating VU data.
Text Box
Editable Text box for labeling DSP configuration.
Selectable font size, color and type.
Superblocks
List of all available Superblocks.
AUTOMATIC GAIN CONTROL (AGC)
The DSP block Automatic Gain Control (AGC) manipulates the audio signal’s dynamics. The AGC’s
task is to control a signal (mostly spoken word) to a defined level (average effective value, target level). This is
accomplished by attenuating signals with levels that are above the target level and amplifying signals with levels that
are below the target level. When compared to a compressor, control intervals are longer because level changes should
not be obvious. An example for using the AGC in spoken word applications could be the automatic level adjustment at
a panel discussion. In music applications the AGC can be used to automatically compensate level differences between
various tracks or songs.
Element
Default Range
Description
This meter indicates by how much the AGC is attenuating or
amplifying the signal level. A green box moving from the 0 dB mark
to the left indicates level reduction. A green box moving from the 0
dB mark to the right indicates level amplification.
-25 dBu -30...0
dBu
THRESHOLD defines the level at which the AGC sets in. The
THRESHOLD value always relates to the set TARGET value.
5.0:1
1:1...15:1 RATIO defines the compression rate, i.e. to what degree the signal’s
level is reduced above the relative threshold level. A ration of 4.0 : 1
represents a signal reduction by factor 4.
+10 dB
0.1... 15
dB
Settable bend of the compression curve below THRESHOLD. A
moderate ratio prevents a drop/leap in amplification at the
THRESHOLD.
0.5 s
0.3... 20 s GAIN INCREASE defines the time interval that it takes the AGC to
raise the signal level to the TARGET.
IRIS-Net
DIGITAL MATRIX | en 368
Bosch Security Systems B.V.
User Manual
2017.05 | 3.20 | F.01U.119.956