MediaPort 200 with Exter
nal DSP with AEC
Program Mix Panel
— Contains the following controls (fader, text box with arrow
buttons, and
Mute
button):
•
USB
Playback
•
HDMI
•
Line
In
(analog line input)
These line inputs typically carry program material. In addition to the gain adjustments
on the
Input
screen that set input gain, the controls in the
Program
Mix
panel adjust
post-input gain. The program mix that is set in this panel is sent to the Line and USB
outputs. Setting the program mix levels at the post-input gain point sends the same mix
to both outputs.
The mix of line input sources made in the program mix panel is also sent to the
Program
fader of the
Mix to Far End
panel and
Near End
room volume fader. These faders
are independent of each other. Adjusting the room volume does not affect the level sent
to the far end, but adjusting the individual program faders affects the mix going to both
the room and the far end.
From Far End Panel
— Contains the
USB Communications
level controls.
The USB Communications fader receives the far end audio signal from the soft codec
conference. This audio is then sent to the MediaPort analog Line output so that it can
be heard in the near end room through a local sound reinforcement system.
Near End Panel
— Contains the
Room
Volume
controls for audio sent to the Line
output, and for the program mix and USB communications audio in the near end room.
Unchecking the
Mix USB Communications
check box at the bottom of the
Near End
panel mutes the USB communications audio to the analog Line output, so that it is only
routed to the AEC ref output.
When the USB communications audio is sent to the Ref output only, the application
is using a DSP in conjunction with the MediaPort 200. In this case, volume control is
performed in the DSP. For this type of application, it is recommended the
Room
Volume
controls be set to
0
dB
, or unity gain. This setting essentially leaves both the Program
Mix and USB Communications levels unaffected by the Room Volume setting.
NOTE:
The
Room
Volume
and the
Mix
to
Far
End
master controls are independent
of each other. Adjusting the
Room
Volume
does affect the mix going to both the
room and the far end.
Mix to Far End Panel
— Contains controls for mic and program levels, which create
the mix that goes to the far end.
Set these levels
during
a call, utilizing verbal feedback from the far end. The signal level
of this audio mix can be viewed using the meters at the bottom of the
USB
panel on
the
Output
screen (on the PCS main window, click the
Audio
Config
button, then the
Output
tab).
If the input gain is set up properly, setting levels higher than 0 dB is generally not
necessary. Program audio can be set to the same level as mic audio, or slightly lower.
Use ducking to lower the program audio level during speech. The ducking processor
returns the program audio to its original level when talking stops.
At the bottom of the
Mix to Far End
panel is the
Mix USB Playback
checkbox.
When this box is checked (default), the USB playback audio is mixed to the USB output
and is sent to the far end. When the box is unchecked, USB playback audio is not sent
to the far end via the USB output.
NOTE:
If using a Web-based soft codec, it may be necessary to unchecked this box,
essentially muting USB playback audio to the far end. This prevents a feedback
loop if USB playback audio is sent to the far end.
MediaPort 200 • with External DSP with AEC Application Setup
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