See the table at right to read the volume
display.
The input LEDs light sequentially to
indicate the approximate volume of the
selected output. Volume is dened as
a percentage of the input audio signal
that is applied to the output. From 0%
of volume, the rst Esc (
>
) button push
applies 5.5% of the input audio signal
and the Input 1 LED begins to blink
slowly. From 5.5% on, each Esc (
>
) push
applies 1.5% more of the input audio
signal to the output:
Push Esc (
>
) button —
5.5% + 1.5% = 7% volume,
indicated by the Input 1 LED
continuing to blink slowly.
Push Esc (
>
) button twice —
7% + 1.5% + 1.5% = 10% volume,
indicated by the Input 1 LED blinking
fast.
Push Esc (
>
) button 19 times —
10% + (19 times 1.5%) = 38.5%
volume, indicated by the Input 1
through Input 4 LEDs lit steadily.
When all input LEDs are lit, the audio
output is 100% of the audio input level.
Another way to think of the volume level is
in terms of the attenuation applied to the
output. Attenuation reduction is indicated
by the lit or blinking input LEDs: when
fewer input LEDs are lit, attenuation is
greater (and the volume is decreased).
At minimum volume, all input LEDs
are unlit and 76 dB of attenuation
is applied to the output. The audio
output is effectively muted.
The first step of volume increase
causes the Input 1 button to blink
slowly. Attenuation is reduced by
13 dB (63 dB of attenuation is
applied to the output).
The second step of volume increase
reduces the attenuation by an
additional 1 dB (62 dB of attenuation
is applied to the output).
Successive steps of volume increase
cause consecutive LEDs to blink
slowly, blink quickly, and then light
steadily.
At full volume, no attenuation is applied to the output and all input LEDs are lit steadily.
87
Input LED
dB of
attenuation
S
F
76
6
54321
87654321
59
Output
volume
0%
5.5%
7%
63
62
8.5%
10%
61
60
11.5%
13%
14.5%
58
57
16%
17.5%
19%
56
55
54
121110
9
1211109
S
F
25
56.5%
58%
29
28
59.5%
61%
27
26
62.5%
15
71.5%
73%
19
18
74.5%
76%
17
16
77.5%
S
F
5
86.5%
86%
9
8
89.5%
91%
7
6
92.5%
S
F
30
49%
50.5%
34
33
52%
53.5%
32
31
55%
20
S
F
64%
65.5%
24
23
67%
68.5%
22
21
70%
10
S
F
79%
80.5%
14
13
82%
83.5%
12
11
85%
0
S
F
94%
95.5%
4
3
97%
98.5%
2
1
100%
5320.5%
S
F
S
F
31%
32.5%
46
45
34%
35.5%
37%
44
43
42
41
38.5%
22%
23.5%
52
51
25%
26.5%
28%
50
49
48
47
29.5%
S
F
S
F
S
F
40%
41.5%
40
39
43%
44.5%
46%
38
37
36
35
47.5%
S
F
= on, = blinking fast, = blinking slowly, = off
Audio Output Volume Settings
MPX 866 A Media Presentation Matrix Switcher • Operation 45
