Arraying - DAS Compact Serie Manual De Usuario

6.5 Arraying

Ideally, only a super-high powered variable coverage speaker
would be used per channel for covering any room. Not
achievable in real life, one must resort to arrays or clusters.
Speakers are arrayed for two reasons:
- To extend the coverage of a system that has too narrow
directivity.
- To increase the sound pressure level.
The tables that follow offer directivity information for different
tight-packed array combinations, separately for horizontal and
vertical. Coverage angle, directivity index (an expression of
the directivity of an array, the more directive the higher) and
on-axis SPL (relative to a single box) results are provided.
For every model, results are provided for a number of array
boxes from 1 to 5, with splay angles from 0 to 50 degrees in
10-degree intervals. Boxes are tight packed. Results are for
the 500 to 8k Hz band, except for subs, where a one octave
100 Hz band is used.
NA
The results are calculated from polars with two degree angular and 1/24th octave
frequency resolution. Active mode was used in active/passive boxes. AUTOPOL, a
platform consisting of custom and customised hardware and software, was used for
automated high-resolution array predictions. Predictions for the 500-8k Hz band may
overestimate the coverage angles, which can reach lower values at specific frequencies.
No. of elements /
Splay angle
variable
0º
10º
20º
30º
40º
50º
Vertical (corresponds to boxes arrayed horizontally on the floor for monitor use)
No. of elements /
Splay angle
variable
0º
10º
20º
30º
40º
50º
No. of elements /
Splay angle
variable
0º
10º
20º
30º
40º
50º
No. of elements /
Splay angle
30
Compact-015
Horizontal
1x 2x
Angle Di SPL Angle Di
90º 9dB +0dB 45º 14dB
45º 13dB
50º 13dB
75º 12dB
85º 11dB
105º 10dB
x1 x2
Angle Di SPL Angle Di
70º 11dB +0dB 25º 15dB
30º 14dB
40º 13dB
70º 11dB
90º 10dB
105º 9dB
Compact-115
Horizontal
1x 2x
Angle Di SPL Angle Di
80º 11dB +0dB 40º 15dB
40º 15dB
45º 14dB
55º 13dB
75º 11dB
100º 10dB
x1 x2
Manual del Usuario / Compact / User's Manual
Example. A 3x2 Compact-2 array (3 columns and 2 rows) with
40-degree horizontal and 30 degree vertical splay (shown on
the illustration).
To find out the coverage of such array, we go to the horizontal
section of the Compact-2 table and look for the 40º/3x cells,
and the 30º/x2 cells on the vertical section. The results (cells
have a grey background) show coverage angles of 165
degrees horizontal and 95 degrees vertical, and an on-axis SPL
of +1 dB (horizontal) and +2 dB (vertical) for a total on-axis
level of +2 dB (0 dB horizontal + 2 dB vertical) above the
level for a single box.
3x
SPL Angle Di SPL
+5dB 15º 16dB +8dB
+5dB 55º 13dB +6dB
+4dB 90º 10dB +4dB
+4dB 125º 8dB +3dB
+3dB 160º 5dB +1dB
+3dB 180º 4dB +1dB
x3
SPL Angle Di SPL
+5dB 15º 18dB +8dB
+4dB 45º 13dB +5dB
+4dB 85º 10dB +4dB
+3dB 120º 7dB +2dB
+2dB 150º 6dB +1dB
+1dB 175º 5dB +1dB
3x
SPL Angle Di SPL
+5dB 20º 18dB +7dB
+5dB 40º 14dB +5dB
+4dB 65º 12dB +5dB
+4dB 110º 9dB +3dB
+3dB 150º 5dB +1dB
+2dB 185º 3dB +0dB
Vertical
x3
4x 5x
Angle Di SPL Angle Di
5º 20dB +9dB 5º 21dB
35º 14dB +7dB 60º 12dB
85º 11dB +5dB 115º 8dB
135º 8dB +3dB 165º 5dB
170º 6dB +2dB 230º 3dB
195º 5dB +2dB 270º 1dB
x4 x5
SPL
+11dB
+7dB
+4dB
+3dB
+2dB
+1dB