3.0 Designing an EVF/EVH Cluster (cont’)
Finally, another way to reduce interference is to apply signal delay of up to 8 milliseconds to one of the two systems. This requires a separate DSP (digital signal processor) drive to the delayed system. Figure 10 shows the dramatic smoothing achieved at 1,250 Hz. Note that the systems are still close together as in Figure 6.
Figure 10:
Horizontal polar response (blue center plot) of two closely clustered 60° x 40° loudspeakers aimed 60° apart, showing the smoothing of
In clusters with more than two systems, adjacent boxes are usually delayed. While the effect can be predicted with appropriate software (such as EASE 4.2), the actual delays are typically established in the field during system setup and commissioning, by ear and measurements.
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