C-Series Input Processing - Polycom SoundStructure C16 Design Manual

C-Series Input Processing

A/D
Mic or Line Analog Parametric
Input Gain Converter Equalization
The input processing on the SoundStructure C-series devices is designed to
make it easy to create conferencing solutions either with or without sound
reinforcement. Each audio input on a SoundStructure C-series device has the
processing shown in the following table.
Input Processing
Up to 8th order highpass and lowpass
1st or 2nd order high shelf and low shelf
10-band parametric equalization
Acoustic echo cancellation, 20-22kHz 200 msec tail-time, monaural or stereo
Automatic gain control: +15 to -15dB
Dynamics processing: gate, expander, compressor, limiter, peak limiter
Feedback Eliminator: 10 adaptive filters
Noise cancellation: 0-20dB noise reduction
Automixer: gain sharing or gated mixer
Signal fader gain: +20 to -100 dB
Signal delay to 1000 msec
The signal processing follows the signal flow shown in the following figure.
Input
1
Processing
Input
2
Processing
Input
N
Processing
Non Linear
Acoustic Echo Noise
Processing
Cancellation Cancellation
Feedback
Cancellation
Each analog input signal has an analog gain stage that is used to adjust the gain
of the input signal to the SoundStructure's nominal signal level of 0 dBu. The
analog gain stage can provide from -20 to 64 dB of gain in 0.5 dB steps. There
is also an option to enable 48 V phantom power on each input. Finally the
analog input signal is digitized and available for processing. The digital signal
Telco
Telco
Telco
Processing
Telco
Processing
Processing
Processing
Output
1
Processing
Output
2
Processing
Matrix
Output
N
Processing
Submix SubMix
Processing
Processsing
AGC Dynamics
Automatic Dynamics
Gain Control Processor
Automixer
Dynamics
Automatic
Automixer
Gain Control Processor
Automatic Dynamics
Automixer
Gain Control Processor
SoundStructure Product Family
Fader Delay Mute
Input to
Fader Delay
Matrix
Input to
Fader Delay
Matrix
Input to
Fader Delay
Matrix
Recording/
Ungated
Conferencing
Sound
Reinforcement
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