Polycom SoundStructure C16 Design Manual page 105

UNGATED - Sound Reinforcement Processing
Mic or Line A/D Parametric
Analog
Input Gain Converter Equalization
Parametric
Equalization
UNGATED - Low Delay Sound Reinforcement Processing
A/D
Mic or Line Analog Parametric
Input Gain Converter Equalization
Parametric
Equalization
following figure.
Non Linear
Acoustic Echo Noise
Processing
Cancellation Cancellation
Feedback
Cancellation
Acoustic Echo Noise Feedback
Cancellation
Cancellation Cancellation
The low delay type corresponds to a processing path that completely bypasses
the processing of the AEC and noise cancellation. Because these processing
blocks are not in the signal path, the signal has lower latency. The AEC and
noise cancellation add 16 msec of latency to the signal path. The resulting pro-
cessing path from bypassing the AEC and noise cancellation paths is shown in
the following figure.
Non Linear
Acoustic Echo Noise
Processing
Cancellation Cancellation
Feedback
Cancellation
Router
Feedback
Cancellation
When the low delay option is selected, the sound reinforcement and sound
reinforcement ungated processing paths will NOT have any echo and noise
cancellation processing. Only the conferencing and ungated conferencing versions
of the input processing will have echo and noise cancellation processing.
These two delay options are summarized in the following table.
Delay Type
Normal
Low delay
The signal processing associated with the low delay option is shown in the fol-
lowing figure for both the ungated sound reinforcement path and automixed
AGC Dynamics
Automatic Dynamics
Gain Control Processor
Router
Automixer
Automatic Dynamics
Automixer
Gain Control Processor
Automatic Dynamics
Automixer
Gain Control Processor
Automatic Dynamics
Processor
Gain Control
AGC Dynamics
Automatic Dynamics
Gain Control Processor
Router
Automixer
Dynamics
Automatic
Automixer
Gain Control Processor
Automatic Dynamics
Automixer
Gain Control Processor
Automatic Dynamics
Processor
Gain Control
Meaning
The signal path includes the latency
associated with the echo and noise
cancellation signal path
The signal path does NOT include the
latency associated with the echo and
noise cancellation signal path. The echo
and noise cancellation blocks are
completely bypassed.
Customizing SoundStructure Designs
Fader Delay Mute
Input to
Fader Delay
Matrix
Input to
Fader Delay
Matrix
Input to
Fader Delay
Matrix
Fader Delay
Mute
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
Recording/
Ungated
Conferencing
Sound
Reinforcement
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