Polycom C16 - Manual (Page 26)

Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12
2 - 12
Recording/Ungated - Sound Reinforcement
Finally, the sound reinforcement recording input includes the echo and noise
cancellation and optional feedback elimination processing as shown in the
following figure.
All three versions (conferencing, sound reinforcement, recording/ungated) of
the input signal processing can be used simultaneously in the matrix. The
conferencing version is typically used to send to remote participants, the
sound reinforcement version is typically used to send to the local loudspeaker
system, and the recording version is typically used for archiving the
conference audio content.
C-Series Matrix Crosspoints
The audio matrix is used to create different mixes of input signals and submix
signals to be sent to output signals and submix signals. Matrix crosspoints gain
values are shown in dB where 0 dB means a signal value is unchanged. For
example, a crosspoint value of -6 dB will lower the signal gain by 6 dB before
it is summed with other signals. The matrix crosspoint gain can be adjusted in
0.1 dB steps between -100 and +20 dB and may also be completely muted. In
addition, the matrix crosspoint can also be negated/inverted so that the
crosspoint arithmetic creates a subtraction rather than an addition. The
inversion technique may be effective in difficult room reinforcement
environments by creating phase differences in alternating zones to add more
gain before feedback.
Matrix crosspoints associated with stereo channels have a balance or pan to
control mapping mono to stereo channels, stereo to mono channels, and stereo
to stereo channels.
The three different versions of the input processing - the ungated,
conferencing, and sound reinforcement - are selected at the matrix crosspoint.
The SoundStructure Studio software allows the user to select which version of
the input signal processing at the matrix crosspoint. As will be shown in
Chapter 4 Creating Designs, the different versions of the input processing will
be represented with different background colors in the matrix crosspoint.
Mic or Line
Input
Input to
Matrix
Input to
Matrix
Parametric
Equalization
A/D
Converter
Analog
Gain
Acoustic Echo
Cancellation
Noise
Cancellation
Automatic
Gain Control
Automixer
AGC Dynamics Fader Delay
Fader Automixer
Automixer
Delay
Automatic
Gain Control
Non Linear
Processing
Feedback
Cancellation
Dynamics
Processor
Dynamics
Processor Fader
Input to
Matrix
Automatic
Gain Control Fader Delay Dynamics
Processor
Delay
Mute
Router
Recording/
Ungated
Conferencing
Sound
Reinforcement
UNGATED - Sound Reinforcement Processing
Parametric
Equalization
Acoustic Echo
Cancellation
Noise
Cancellation
Automatic
Gain Control
Fader Delay Feedback
Cancellation
Dynamics
Processor
Mute