Using Automatic Gain Control (Agc) - Polycom SoundStructure C16 Design Manual

Ungated Conferencing Signal Path
UNGATED - Conferencing Processing
Mic or Line Analog A/D Parametric
Converter
Input Gain Equalization
Parametric
Equalization
After you select the conferencing ungated type in the Channels page, select the ungated signal path in the
matrix, as shown in the following figure. This selection chooses the conferencing ungated signal path and
enables you to enable noise cancellation on that input signal.
Ungated Signal Path in Matrix

Using Automatic Gain Control (AGC)

Automatic gain control is used to automatically adjust the gain of audio signals so that the average signal
level is close to the SoundStructure nominal signal level of 0 dBu. You can use the AGC processing on any
input signal.
AGC is typically used on microphone input signals to compensate for local talkers that are different
distances from their microphones or telephone input signals to compensate for varying telephone levels.
The AGC system is designed to adapt the gain only when valid speech is present.
You can turn the AGC on or off with the AGC enable button. When the AGC is enabled, you can view the
current AGC gain (or attenuation) from the AGC meter and the text box next to the AGC meter.
Polycom, Inc.
Non Linear
Acoustic Echo Noise
Processing
Cancellation Cancellation
Feedback
Cancellation
Acoustic Echo Noise Non Linear
Cancellation Cancellation Processing
AGC Dynamics
Automatic Dynamics
Gain Control Processor
Automixer
Automatic Dynamics
Automixer
Processor
Gain Control
Automatic Dynamics
Automixer
Gain Control Processor
Automatic Dynamics
Gain Control Processor
Fader Delay Mute
Input to
Fader Delay
Matrix
Input to
Fader Delay
Matrix
Input to
Fader Delay
Matrix
Fader Delay Mute
Recording/
Ungated
Conferencing
Sound
Reinforcement
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