Menu
L-Acoustics dV-DOSC Operator's Manual
Also see for dV-DOSC: Operator's manual
                                                                                                                                 | |
Contents
| 
dV-DOSC dV-SUB Manual V2.0 Nov 2001 633. ELEMENTS OF SOUND DESIGN3.1 MULTIPLE ARRAY CONCEPTSReducing Array InteractionIt is well known that the collective radiation of sound by a number of loudspeakers located close toeach other results in interference that creates frequency-dependent directivity lobes. The onlycoherent way to couple loudspeakers is to meet Wavefront Sculpture Technology criteria, which,for the case of dV-DOSC is met in the vertical domain.When the horizontal coverage of a dV-DOSC array (120° nominal, 100° effective) is not sufficient,the solution is not to place a second array directly beside the first one. The correct approach is toutilize a second array which is focused on another portion of the audience and spaced at least 6-7meters (approximately 20 ft) away from the first array.Given this separation, interference only occurs in the low frequency range and there are no audibleintelligibility losses for two reasons: 1) the first main cancellation is shifted lower in frequency(example, 24 Hz for 2 arrays of the same size, spaced 7 metres) and tends to be masked or filled inby room reverberation; 2) by focussing the arrays at different panning angles, comb filteringinteraction is lessened since their overlap region is reduced. In addition, the ear cannot resolvetightly spaced comb filtering notches at higher frequencies throughout the overlap region.The array closest to the stage is usually the larger of the two arrays. This array is considered as thetime reference and any other array is delayed with respect to it. This is valid for arrays fed with thesame signal (in a stereo configuration, it is obvious that the left array is not delayed with respect tothe right one or vice-versa).Experience has shown that this is a very flexible approach that can cover any type of audience. Anadditional advantage of multiple arrays is improved resistance to wind effects in open-air situations.Another benefit is improved perception of stereo effects throughout the audience area – somethingwhich should not be limited to just the mix position (i.e., arrays can be run in cross-panned stereowith L-L (right), L (left), R (right) and R-R (left)).Beyond the basic solution of coverage problems, multiple source arrays open up many possibilitiesfor creating a spatial soundscape, thus providing a powerful tool for sound design and creativity.Achieving Optimum CoverageUsing the isocontour drawn on a blueprint or the data provided in ARRAY 2000 (H-ISOCONTOUR),it is easy to achieve correct horizontal coverage for a complete system consisting of multiple V-DOSC and/or dV-DOSC arrays. Parameters for each array such as spatial coordinates, axial directionand output level are first chosen by the sound designer and entered in the ARRAY 2000 spreadsheetwith respect to the basic geometry of the audience.The displayed horizontal isocontours should overlap to a certain extent and cover the majority ofthe audience. The amount of overlap will depend on the tradeoffs between stereo perception andintelligibility. The remaining areas should be covered with fill speakers such as ARCS, MTD115a,MTD112, MTD108a or EX112 loudspeakers. |
Related manuals for L-Acoustics dV-DOSC
Product
Learn More
Legal
Copyright © 2024 OneStart. All Rights Reserved