Extron electronic MAV 48 Adjusting input audio gain and attenuation, Consumer VCR Audio Inputs

Adjusting input audio gain and attenuation

Audio/video switchers have input audio gain and attenuation adjustments. In Audio Setup mode the audio gain or attenuation 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 (figure 3-31).

dBu	dBV		dBu	dBV
			+10	+8
+10	+8
			+7	+5
+7	+5		+4	+2
+4	+2		+1	-1
+1	-1		-2	-4
-2	-3	Consumer VCR	-5	-7
-5	-7		-8	-10
-8	-10	Audio	-12	-14
-12	-14	Inputs	-18	-20
-18	-20

Low Audio																		Output
																		Level
Output Level
																		MAV SERIES
				INPUTS								OUTPUTS						AV MATRIX SWITCHER
1	2	3	4	5	6	7	8	1	2	3	4	5	6	7	8	ENTER	PRESET	I/O
																		VID +dB
																		AUD -dB
																		AUDIO SETUP

		Audio	MAV 88 AV Series Switcher	Audio System
dBu	dBV	Inputs
+10	+8			No noticeable volume
+7	+5
+4	+2		differences between sources
+1	-1
-2	-3
-5	-7
-8	-10
-12	-14
-18	-20

High Audio

Output Level

Pro CD Player

Figure 3-31 — Audio gain and attenuation

In Audio Setup mode, whichever input is selected for adjustment is automatically tied to output 1. You can 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 chapter 4, “Remote Operation”).

MAV 44 / 48 / 84 / 88 Matrix Switchers • Operation 3-19