Polycom SoundStructure C16 Design Manual page 291

Integrating The Polycom Touch Control with SoundStructure Systems
Adjusting the volume on the Polycom Touch Control adjusts the value of the
fader parameter of the channel "Amplifier". This event may be customized to
support different channels or different channel names. "Amplifier" is the
name used by default.
_Polycom HDX to SST volume
Maps Volume to "Amplifier" fader
Unmute
SoundStructure
Volume
By default, SoundStructure Studio will automatically set the fader min of the
"Amplifier" channel to -31 and the fader max to +20. This maps the volume
range of the Polycom Touch Control slider from 0 to 51 to the fader range of
-31dB to +20dB as shown in the following figure.
Volume = 0 set fader "Amplifier" -31
Volume = 51 set fader "Amplifier" 20
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