Extron Electronics MVX 44_48_84_88 Series User Guide - Manual (Page 29)

Adjusting Input Audio Gain and Attenuation
Switchers have input audio gain and attenuation adjustments. In Audio Setup mode,
the audio level of each input can be adjusted through a range of –18 dB to +10 dB. This
adjustment range ensures that there is no noticeable volume difference among sources. It
also eliminates the need for separate preamps or attenuators when used with professional
(higher line level) and consumer (lower line level) audio equipment (see
figure 12 ).
Audio
Inputs
Audio
Inputs
Laptop
No noticeable volume
differences between sources
Audio System
Computer
+2
-1
-3
-7
-10
-14
Low Audio
Output Level
+5
+8
+4
+1
-2
-5
-8
-12
-20 -18
+7
+10
+2
-1
-4
-7
-10
-14
Output
Level
+5
+8
+4
+1
-2
-5
-8
-12
-20 -18
+7
+10
dBv dBu
High Audio
Output Level
dBv dBu
+2
-1
-3
-7
-10
-14
+5
+8
+4
+1
-2
-5
-8
-12
-20 -18
+7
+10
dBv dBu
MVX VGA A Series Switcher
DAS101 CM
DAV101CM VGA LINE DRIVER
VIDEO INPUT POWER
MVX SERIES VGA/AUDIO MATRIX SWITCHER I/O
AUD AUDIO SETUP
PRESET
VID IR +dB
-dB
ENTER 2 7 6 5 2 4 1 INPUTS OUTPUTS 8 3 1 8 6 5 4 3 7
Figure 12. Audio Gain and Attenuation
In Audio Setup mode, the input that is selected for adjustment is automatically tied to
output 1. Connect a VU meter or an audio system to output 1 to measure or monitor the
audio while you perform adjustments.
There are two ways to measure the audio level during audio setup:
• Monitor the input audio level indicator (Power LED) on the front panel.
• Connect a VU meter to output 1 and, if necessary, temporarily set the output 1 level
to the consumer (-10 dBV) level (see the
Audio output level SIS commands in the
“Remote Operation” section).
The input audio gain or attenuation can be adjusted from the front panel or by using the
Extron Matrix Switchers Control Program or the SIS.
1. Apply audio signals to all inputs to be adjusted.
2. Press and hold the Audio Setup (I/O) button until the Audio Setup LED lights. Release
the Audio Setup button.
3. Press and release an input button to select an input. The selected input can be adjusted
and is tied to output 1 for measurement or monitoring.
a. The Output 1 through Output 3 LEDs display the approximate audio gain or
attenuation for the selected input. The +dB and –dB LEDs display the polarity
(+ [gain] or – [attenuation]).
• Each Output 1 through Output 3 LED indicates a range of 6 dB when lit:
• Output 1 LED off = 0 dB to 5 dB 2 1 3
0 – 5 db
6 – 11 db
12 – 17 db
18 db
• Output 1 LED lit = 6 dB to 11 dB
• Output 1 and 2 LED lit = 12 dB to 17 dB
• Output 1 through Output 3 LEDs lit = 18 dB
• The +dB LED on indicates a positive (gain) level. The –dB LED on indicates a
negative (attenuation) level. Both LEDs on indicate 0 dB.
MVX 44 / 48 / 84 / 88 VGA Matrix Switchers • Operation 23