Nexo RS - Manual (Page 33)

G ENERAL GUIDELINES FOR SUBWOOFER DESIGN Page 33/54
6.2 Gradient Subwoofers benefits
Gradient subwoofers can provide up to 15 dB front to rear average
attenuation (Please refer to Ray Sub technical note for in-detail explanation
on gradient subwoofers).
Low frequency level on stage is therefore significantly reduced on stage, and
in the neighbouring environment in open air venues.
Because of their directional pattern, Gradient subwoofer are also less
sensitive to room eigen modes.
6.3 Monophonic Design
Left and Right subwoofer arrays can be merged into a monophonic system so that interferences no
longer exist.
When using few cabinets, this can be done by installing these cabinets at the centre front stage. If
cabinets are set on the ground in front of the stage, level discrepancy from first to last rows will be
important. Flying cabinets above centre stage will reduce first to last rows discrepancies significantly.
CENTRE STACKED DIRECTIONAL SUBWOOFER CENTRE FLOWN DIRECTIONAL SUBWOOFER
When using a larger amount of cabinets, these can then be installed all across the stage provided
distance between units does not exceed half the wavelength of the upper frequency limit (1.7m/5.6ft at
100 Hz). Array coverage can then be adjusted geometrically (by curving the array horizontally so that it
matches the audience area, which creates an asymmetrical front stage to rear stage pattern with a “hot”
point on stage) or electronically (by implementing a delay that increase from the centre to the sides,
which creates a symmetrical pattern front to rear). In both cases, omnidirectional subwoofers should be
avoided so low frequency that level on stage does not exceed level in the audience.
CURVED SUBWOOFER ARRAY ACROSS STAGE STRAIGHT DELAYED SUBWOOFER ARRAY ACROSS STAGE