Polycom SoundStructure C16 Design Manual page 105

The normal delay type for the Sound Reinforcement ungated type corresponds to the processing paths that
was defined previously and is shown in the following figure.
Sound Reinforcement Ungated Normal Delay Type Processing
UNGATED - Sound Reinforcement Processing
Mic or Line Analog A/D Parametric
Input Converter Equalization
Gain
Parametric
Equalization
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
processing path from bypassing the AEC and noise cancellation paths is shown in the following figure.
Low Delay Type Processing Bypassing AEC and Noise Cancellation
UNGATED - Low Delay Sound Reinforcement Processing
Mic or Line Analog A/D Parametric
Converter
Input Gain Equalization
Parametric
Equalization
Note: No Echo and Noise Cancellation when Low Delay is Selected
When the low delay option is selected, the sound reinforcement and sound
reinforcement ungated processing paths do not have any echo and noise
cancellation processing. Only the conferencing and ungated conferencing versions
of the input processing have echo and noise cancellation processing.
These two delay options are summarized in the following table.
Normal and Low Delay Type Options
Delay Type Meaning
Normal The signal path includes the latency associated with the echo and noise cancellation signal
path
Low delay 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.
Polycom, Inc.
Non Linear
Acoustic Echo Noise
Processing
Cancellation Cancellation
Feedback
Cancellation
Acoustic Echo Noise Feedback
Cancellation Cancellation Cancellation
Non Linear
Acoustic Echo Noise
Processing
Cancellation Cancellation
Feedback
Cancellation
Router
Feedback
Cancellation
AGC Dynamics
Automatic Dynamics
Gain Control Processor
Automixer
Automatic Dynamics
Automixer
Gain Control Processor
Automatic Dynamics
Automixer
Gain Control Processor
Automatic Dynamics
Gain Control Processor
AGC Dynamics
Automatic Dynamics
Gain Control Processor
Router
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
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
105