L-Acoustics SB118, User Manual

Page: 18 / 52

$$ $$ $$ $$ !% $ !% $ !% $ !% $
!
! !
!
& "$!
+
+ +
+
7.3 “CARDIOID” mode
7.3.1 Description
The ‘‘CARDIOID’’ mode consists in arraying the SB118 enclosures with some of them being reversed from front to
rear so as to obtain a cardioid coverage pattern, providing a maximum rejection to the rear. The associated cardioid
presets are available in both LA4 and LA8 libraries.
The basic arrays contain four enclosures. Several basic arrays can then be put together to form taller ones. The
recommended basic cardioid arrays are the “line-up”, “block”, and “on-end” arrays (see also Figure 10):
•
All arrays provide equivalent front SPL level and equivalent rear rejection.
•
The “line-up” array provides symmetric coverage pattern in the horizontal plane.
•
The “block” and “on-end” arrays provide asymmetric coverage pattern in the horizontal plane with an
additional rejection to the reversed sub side.
•
The “on-end” array also provides directive coverage pattern in the horizontal plane, in line with the array
length.
If two (or more) basic arrays are intended to be used in close proximity from each other it is
recommended to set the distance at 0 (as shown in Figure 12).
If it is not possible, the maximum distance between two acoustic centers is 2.8 m in the
32-60 Hz frequency bandwidth, and 1.7 m in the 32-100 Hz bandwidth.
Figure 10: SB118 basic cardioid arrays
LINE UP ON END BLOCK
!
IMPORTANT