VAR4 / VAR12 / VAR20 - Operation Manual
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18.2 Monitoring
18.2.1 Amplifier
and
Input Level Monitoring
The amplifier output to any loudspeaker circuit, or any VAR Router audio input or DVA message can be
audibly monitored via the front panel loudspeaker and its audio level displayed on the LCD display.
L
The audio monitoring functions are also accessible by pressing the front panel ‘AUDIO MON’
key.
Audio monitoring affects only the LCD display of the unit, i.e. all fault-monitoring activities continue to take
place in the background. The status of the LEDs and external outputs are unaffected.
Note:
When monitoring an amplifier, the audio monitor facility actually monitors the audio feeding the
speaker circuit associated with a particular amplifier. If an amplifier has failed and a standby is in
operation, then it is possible to still monitor the audio associated with that speaker circuit, i.e. the
audio being monitored is from the standby amplifier, which is feeding the failed amplifier’s speaker
output.
In order to monitor an amplifier output or an audio input proceed as follows.
1. Select
Tests
Æ
Monitor
Æ
Audio
.
2. Scroll and select a mainframe/slot or an input from the list:
[Framenn/Sxx - ]
Note:
Only configured mainframe/slots are displayed.
Mainframe and slot description will be displayed on the right side, if defined.
All VAR Router inputs (Mic/Line, DVA, and background music) are displayed.
The current selected Music input source can be monitored in the case where both Music A and
B are used with switching between them.
3. A simple bargraph is displayed:
>>>>>-30... -20... –10... 0...dB(100V)
Note:
When monitoring inputs, the level displayed is dB (FS). This is dBs relative to digital Full Scale.
Typically the input gain should be set so that input signal peaks are in the range –10 to
–20dBFS to allow enough headroom within the VAR Router.
The monitored audio level is adjustable by the rotary encoder. Note that this volume control
affects only the monitor audio level and not the level of the alarm sounder which shares the
same amplifier and speaker.
The amplifier currently being monitored is displayed on the LCD and the VAR Router causes its
associated ‘select’ LED to be illuminated.
Characters are overwritten by >>>> in step with the measured audio level.
A warning message will be displayed if an unused input is selected.
4. The system remains monitoring whilst within this menu with regular display refreshes and finishes when
the menu times out, the BACK key is pressed, or if any new faults occur.
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