Polycom C16 - Manual (Page 36)

Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12
2 - 22
microphone audio to paging zones that are not acoustically coupled to the
microphone. This is the default processing for microphone inputs when the
automixed version of the signal is selected.
Sound Reinforcement Version
The sound reinforcement version is processed with the parametric
equalization, noise cancellation, optional feedback elimination processing,
automatic gain control, dynamics processing, automixer, fader, delay, and
input mute. This is the path that is typically used for sending local audio to
loudspeakers in the room for sound reinforcement.
The automatic gain control on the sound reinforcement path is different from
the automatic gain control on the noise cancelled version of the signal in that
the sound reinforcement automatic gain control will not add gain to the signal.
In other words, the sound reinforcement AGC will only reduce the gain of the
signal and will not add gain to the signal. This restriction on the sound
reinforcement AGC is to prevent the automatic gain control from reducing the
available potential acoustic gain before the onset of feedback.
Recording/Ungated Version
The recording version of the processed input signal is specifically designed to
not include any gain sharing or gated-style of automatic microphone mixing
processing. The recording/ungated version of the input is used for recording
applications or in any application where an un-automixed version of the input
signal is required.
Mic or Line
Input
Input to
Matrix
Input to
Matrix
Parametric
Equalization
A/D
Converter
Analog
Gain
Noise
Cancellation
Automatic
Gain Control
Automixer
AGC Dynamics Fader Delay
Fader Automixer
Automixer
Delay
Automatic
Gain Control
Feedback
Cancellation
Dynamics
Processor
Dynamics
Processor Fader
Input to
Matrix
Automatic
Gain Control Fader Delay Dynamics
Processor
Delay
Mute
Router
Recording/
Ungated
Noise Cancelled
Sound
Reinforcement
SR-Series Noise Cancellation Input Processing
Parametric
Equalization
Noise
Cancellation
Automatic
Gain Control
Fader Automixer Delay
Dynamics
Processor
Mute
Mic or Line
Input
Input to
Matrix
Input to
Matrix
Parametric
Equalization
A/D
Converter
Analog
Gain
Noise
Cancellation
Automatic
Gain Control
Automixer
AGC Dynamics Fader Delay
Fader Automixer
Automixer
Delay
Automatic
Gain Control
Feedback
Cancellation
Dynamics
Processor
Dynamics
Processor Fader
Input to
Matrix
Automatic
Gain Control Fader Delay Dynamics
Processor
Delay
Mute
Router
Recording/
Ungated
Noise Cancelled
Sound
Reinforcement
SR-Series Sound Reinforcement Input Processing
Parametric
Equalization
Noise
Cancellation
Automatic
Gain Control
Feedback
Cancellation
Fader Automixer Delay
Dynamics
Processor
Mute
The automatic gain control on the sound reinforcement processing path will not add
gain to the signal, it will only reduce the gain of the signal.