Flown Cardioid Configurations; Array Configurations - JBL VTX Series User Manual

12 - FLOWN CARDIOID CONFIGURA TIONS
B18 subwoofers can be suspended in cardioid configurations using VTX A8 suspension accessories like the VTX A8 AF Array Frame,
the VTX A8 MF Mini Frame or the VTX A8 SB Suspension Bar. This chapter outlines best practices for using the B18 in flown cardioid
configurations.
12.1 ARRA Y CONFIGURA TIONS
When used in flown cardioid configurations, B18s should be used in blocks of three or four, and when possible, in arrangements that are
symmetric, top to bottom. Symmetry ensures that the pattern produced by the array is axially symmetric with the physical array, allowing
for more predictable aiming and coverage. Non-symmetric arrangements can be created, but should always be modeled in LAC-3 first
to ensure that the none of the audience sits in the array's cancellation areas.
The example below contrasts the standard cardioid coverage of an F-R-F array with that of a potentially problematic F-F-R array. The
SPL maps show that the F-F-R array, with a rear-facing subwoofer at the bottom, tilts the front coverage upwards and places a rejection
zone where audience areas can fall within it.
Example 1: (3) VTX B18 symmetrically arranged (front-rear-front)
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Example 2: (3) VTX B18 in an asymmetric configuration (front-front-rear)
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VTX B18 | User Manual
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