Polycom C16 - Manual (Page 121)

Customizing SoundStructure Designs
5 - 41
Camera Activity Time
Camera Activity Time specifies how long the microphone must be considered
active before a camera indicator is set. The camera indicator is a status mes-
sage that can be used with an external control system to indicate that a
particular microphone is active. Shorter times mean the indicator will be
easier to set based on local talker activity. Longer times mean that it will take
longer before the camera gating activity indictor is triggered.
Priority Attenuation
Each automixer group can have a priority attenuation setting, in dB. A value
of 0 means the higher priority microphone will come first in the ordering of
which microphones to gate on, but will not otherwise attenuate a lower prior-
ity microphone. A priority attenuation value greater than 0 causes the lower
priority microphones to be attenuated (in addition to any NOM limit effects)
by the priority attenuation when a higher priority microphone is active.
Gain-sharing automixer groups can use the priority attenuation to simulate a
“soft chairman'' priority ducking.
Off Attenuation
Off Attenuation is the amount of attenuation applied to gated channels when
they are not active. This should be set high enough that inactive channels don't
contribute too much noise and reverberation to the mix. The ideal value for
this parameter may increase with the number of microphones in the system.
The default value is 15 dB.
Decay Time
Decay time is the amount of time a gated channel takes to ramp its gain down
from open (0 dB) to its off attenuation. This should be set long enough to pro-
vide a smooth transition as the talker stops speaking.
Gating Indicators
Channel activity status (the gate light for each microphone) is available for
microphones regardless of whether they are in a gain sharing automixer group
or a gating automixer group. The gating status lights can be useful for output
to channel activity LEDs via the logic outputs and control system displays.
Camera activity is similar to channel activity, but has some additional time
that the microphone must be gated before the camera gating indicator is made
active. The camera gating status is intended to be used with logic outputs or
control systems that interface to a camera positioning system that can have
various presets according to which microphones are active.
Adaptive Threshold
Adaptive threshold is the level in dB relative to its noise floor a signal must