Polycom Vortex EF2241, Application Note

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The sound effects volume control can be adjusted in the System Info, Admin Setup, Phone Audio
page.
2. If the ViewStation EX is turned off either through the power switch or unplugged from the wall
while the codec is still connected to the Vortex device via the input and output audio cables, a
loopback will occur in the codec. This means that a portion of the audio signal that is sent to the
codec from the Vortex device will be coupled into the signal that is sent from the codec to the
Vortex device. This will cause the local room to hear a reinforced version of their own speech via
the local room loudspeakers. Our recommendation is to leave the codec power on all the time;
however, if the codec must be powered down, we recommend muting either the output channel of
the Vortex device that will feed the input of the codec or the input channel of the Vortex device that
is connected to the output of the codec.
Polycom ViewStation FX
C
ONNECTING THE
V
IEW
S
TATION
FX I
NPUTS AND
O
UTPUTS
In order to send and receive audio to the Polycom ViewStation FX codec, you need to observe the following
procedure:
1. Connect one of the Outputs of the Vortex device to the mixer input of the codec. By default,
Outputs A-C of the Vortex device are mix-minus versions of the Inputs A-C signals.
2. Connect the auxiliary line level output of the codec to one of the line level inputs of the Vortex
device (Inputs A-D). You may use one of the Mic/Line level inputs, but you need to disable all
processing on that input (AEC, AGC, NC, Automixer), disable Phantom Power, and set the input to
line level versus the default of mic level.
Follow the diagram below to make the proper physical connections to the codec. Do not
use any other audio inputs or outputs as they could cause an audio loopback to occur
within the codec.
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