Polycom SoundStructure C16 Design Manual page 170

Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12
In the third step, the equipment is selected. In this case a C12 is required and
will have three additional analog inputs available that can be used once the
system has been designed.
In the final step, offline operation will be selected and the resulting project will
be created. The channels page associated with this project is shown in the
following figure.
Notice that the digital microphone arrays are shown just as any other audio
channel in the system. Although the signal level meters are active for the HDX
microphones, one difference between an analog microphone input and a
digital microphone array input to SoundStructure is that the analog gain slider
is not present on the digital microphones as shown in the following figure. The
slider is not present because it does not affect the signal level coming in from
the microphone array as the signal is already digitized in the microphone
array and does not pass through the SoundStructure's analog gain stage.
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