Dynamics Processing - Polycom SoundStructure C16 Design Manual

Dynamics Processing

The range of the AGC can be adjusted by expanding the AGC control and
adjusting the maximum and minimum gains. By default the maximum and
minimum gain are set to 6 and -6 respectively on microphone and telephony
signals.
The maximum AGC value specifies the maximum amount of gain the AGC can
apply to increase the input signal level as the AGC tries to reach the Sound-
Structure nominal signal level.
The minimum AGC value specifies the maximum amount of attenuation the
AGC can apply to attenuate the input signal as the AGC tries to reach the
SoundStructure nominal signal level.
If the input is a stereo virtual channel, the AGC gain for both underlying left
and right physical channels will use the same gain, ensuring that the stereo
image is preserved.
To operate the AGC with a target level different from 0 dBu, set the AGC min-
imum and maximum range to the desired range and then adjust the input
fader to the desired target level above or below the 0 dBu nominal signal level
of the SoundStructure devices. This allows the AGC to adapt to the 0 dBu
nominal level and then the fader settings will offset the 0 dBu level to the set-
ting on the fader.
Dynamics processors, also known as non-linear processors, are used to reduce
the dynamic range, or amplitude, of input or output signals and are often used
on sound reinforcement systems to prevent clipping audio amplifiers.
Dynamics processors are similar to automatic gain controllers, but are typi-
cally faster acting and can be used with program audio and other fast changing
input signals.
SoundStructure devices include the following styles of look-ahead dynamics
processing.
• Peak Limiter
• Limiter
• Compressor
• Expander
Customizing SoundStructure Designs
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