L-Acoustics V-DOSC, Operator'S Manual

Page: 15 / 158

L-ACOUSTICS V-DOSC Manual Version 4 6/29/2005 Page 15 of 158
The configuration of transducers in V-DOSC is symmetrical with respect to the plane of propagation
of the radiated wavefront, i.e., the plane bisecting the horizontal coverage angle. High frequency
transducers loaded by DOSC waveguides are located in the middle, mid frequency transducers are on
both sides of the high section, and low frequency transducers are laterally positioned on both ends.
Such a configuration is described as having coplanar symmetry.
Coplanar symmetry is the cylindrical domain equivalent of the coaxial arrangement
*
for individual
sound sources. Essentially, coplanar symmetry provides even coverage at any listening angle over a V-
DOSC array’s 90° horizontal coverage pattern, eliminating off-axis cancellations and polar lobing
effects at crossover frequencies. Coplanar symmetry produces a stable, symmetric horizontal
coverage pattern allowing simple, easy-to-use software tools to be used for horizontal coverage
prediction. Psychoacoustically, coplanar symmetry is largely responsible for the exceptional stereo
imaging properties that are characteristic of V-DOSC. Other practical benefits of the coplanar
symmetric configuration include the fact that there is no need to fly mirror-imaged L/R arrays plus
rigging issues are further simplified since the enclosure’s centre of gravity is also symmetric.
Figure 3: Coplanar Symmetry of V-DOSC
*
Distributed sound reinforcement using coaxial loudspeaker technology is L-ACOUSTICS’ other approach to sound
reinforcement. Either we respect WST criteria to obtain coherent coupling between individual sources and create a
single coherent line source (as for V-DOSC, dV-DOSC, KUDO, ARCS) or we separate individual, coherent sources
(MTD or XT coaxial loudspeakers) in a manner so that desired audience coverage is achieved while the effects of
audible interference are reduced. For more details on the benefits of coaxial loudspeaker technology and distributed
sound design techniques, please refer to the MTD or XT User Manuals (available for download on:
www.l-
acoustics.com ).