Eds Example - With Delays - JBL VTX Series User Manual

13.2 EDS EXAMPLE - WITH DELA YS
The delay calculation function of LAC-3 can generate delay values for each B18 cluster that electronically "curve" the array to a pre-
determined angle that "opens" its coverage wider. Delay values generated by LAC-3 for an opening angle of 60 degrees produce array
coverage as shown in the SPL map below. As can be seen, the widened coverage reaches more parts of the venue.
46
44
42
40
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
0 4 8 12 16
The illustration below shows the delay values generated by LAC (for a 60° angle) and the "virtually" arced array based on the delays.
Delay values for different coverage angles and cluster spacing can be generated in LAC-3. Care should be taken not to steer an array
so strongly that it significantly reduces energy at on-axis positions.
6.7 ms 3.2 ms
B18 B18
Compact Single 18" Subwoofer Compact Single 18" Subwoofer
IN/OUT IN/OUT IN/OUT IN/OUT
A B SN A B SN
Channel Selection Channel Selection
Real Array Virtual Array
20 24 28 32 36 40
1.0 ms 0 ms
B18
Compact Single 18" Subwoofer
IN/OUT IN/OUT
A B SN
Channel Selection
44 48 52 56 60
0 ms
B18 B18
Compact Single 18" Subwoofer Compact Single 18" Subwoofer
IN/OUT IN/OUT IN/OUT IN/OUT
A B SN A B SN
Channel Selection Channel Selection
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VTX B18 | User Manual
64 68 72 76 80
1.0 ms 3.2 ms
B18 B18
Compact Single 18" Subwoofer Compact Single 18" Subwoofer
IN/OUT IN/OUT IN/OUT IN/OUT
A B SN A B SN
Channel Selection Channel Selection
120
115
110
105
100
95
90
85
80
84 88
6.7 ms
B18
Compact Single 18" Subwoofer
IN/OUT IN/OUT
A B SN
Channel Selection