GUIDE TO INSTALLATION AND OPERATION
XVP-3901 |
49
96 to 12 dB in 0.5 dB steps. For non-PCM audio, the level value is overridden to 0 dB.
Mute
(speaker button): Mutes the selected audio channel
Phase Invert
: When checked, inverts the selected audio channel phase.
Lock
: “Locks” both channel sliders together for levels and delay (coarse only), so that moving one slider
moves the other one as well.
Fixed Delay sub-tab
: although the XVP-3901 automatically
matches audio and video throughput timing, provision is
made for the user to insert an audio delay offset from the
nominal value, in order to deal with problems such as lip-sync
errors and audio phase alignment in the incoming feed. For
each channel, two sliders allow the delay to be adjusted.
•
Coarse
– adjusts the delay in milliseconds, over a
range of values that depends on the Additional Frame
Delay set on the timing tab in the Video Output group
(see page 31), as follows:
Additional
Adjustment
Adjustment
Frame Delay Range Range
(59.94 Hz)
(50 Hz)
0
0 to 2000 ms
0 to 2000 ms
1
-33 to 2000 ms
-40 to 2000 ms
2
-66 to 2000 ms
-80 to 2000 ms
3
-99 to 2000 ms
-120 to 2000 ms
…
…
…
15
-500 to 2000 ms
-600 to 2000 ms
•
Fine
– adjusts the delay in audio sample increments,
from -100 to +100 samples.
Silence sub-tab
This tab sets the card’s behavior in the event of a loss or
absence of audio signal. The Signal Presence indicators are
then triggered according to these setting
s:
Silence Detect:
select which audio channels to monitor for
audio silences by checking their boxes. This enables the
signal presence indicators to change color when there is no
signal present which activates the audio silence alarm.
Otherwise, when checkboxes are not checked, the signal
presence indicator turns grey and the audio silence alarm is
not activated
Threshold
: Signal absence is declared when the signal level
is lower than the signal threshold for a duration longer than
the No Signal Delay. The threshold can be set to
-72, -66, -60,
-54, -48
dBFS. The default value is –60 dBFS.
No Signal Delay:
The period for which signal must be
continuously absent before an alarm can be triggered can be
adjusted from 3 to 255 seconds in preset steps: 3, 5, 7, 10,
15, 20, 30, 40, 50, 60, 90, 120, 180, 210, 240, 255 sec. The default value is set to 15 seconds.
Figure 5.36
Audio Processing - Fixed Delay sub-tab
Figure 5.37
Audio Processing - Silence sub-tab
