Understanding Soundstructure Sr-Series Products - Polycom SoundStructure C16 Design Manual

back to the remote participants. The AEC
remote talker so the audio is not sent back to the remote talker.
SoundStructure C-Series Acoustic Echo Cancellation Process
Local Room
LocalTalker
Acoustic echo cancellation processing is only required on the inputs that have microphone audio connected
which can potentially hear both the local talkers' speech and the acoustic echo of the remote talkers'
speech.
In order for the local acoustic echo canceller to cancel the acoustic echo of the remote participants, it must
have an echo canceller reference defined. The echo canceller reference includes all the signals from the
remote site that needs echo canceling. In the above figure, the AEC reference for both the local and remote
rooms includes the audio that is played out the loudspeaker. See
Conferencing Systems
cancellation.
Within SoundStructure devices, the acoustic echo canceller on each input can have either one or two AEC
references specified per input signal. For traditional monaural audio or video conferencing applications, only
one acoustic echo canceller reference is used which is typically sent to the single loudspeaker zone. See
the Creating an Eight Microphones, Video, and Telephony Application Conferencing System
Advanced Applications
Applications that have two independent audio sources played into the room such as stereo audio from a
stereo video codec require two mono AEC references, or one stereo AEC reference. See
Microphones and Stereo Video Conferencing System
You can create an acoustic echo canceller reference from any output signal or any submix signal. For a
SoundStructure C16 device, this means that there are 32 possible echo canceller references (16 outputs +
16 submixes) that you can define and select.

Understanding SoundStructure SR-Series Products

The SoundStructure SR12 has a similar architecture to the SoundStructure C-series. While the
SoundStructure SR12 does not include acoustic echo cancellation processing, the SR12 does include noise
cancellation, automatic microphone mixing, matrix mixing, equalization, feedback elimination, dynamics
processing, delay, and submix processing.
Polycom, Inc.
Local Room
AEC reference for local room
for additional information on audio conferencing systems and acoustic echo
for an example.
in the following figure removes the acoustic echo of the
AEC reference for remote room
Appendix C: Designing Audio
in Creating Advanced
Remote Room
Remote Talker
in Creating
Creating an Eight
Applications.
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