Optimizing scattering from stage canopy arrays: determining density, size, shape and position.

Abstract

The reflecting surfaces around a stage area play an important part in enabling ensemble among musicians. Energy must be reflected back to the stage to enable musicians to hear themselves and others and so achieve the correct rhythm, intonation, balance, and timbre. Gade summarized the current understanding of stage acoustic requirements; in particular, when stage reflections should arrive and how loud they should be. The study presented in this paper concentrates on the design of overhead canopy arrays, in particular, investigating effects of density, size, shape, and position. This aspect has surprisingly been little researched, although work by Rindel investigated similar questions to those being posed here. The advent of modern computer processing power allows stage canopy arrays and towers to be optimized using iterative algorithms, based on wave-based acoustic prediction models. A shape optimization program has been developed to optimize both the shape and tilt of overhead canopy arrays. Previously, the height and density have been specified based on experimental evidence and lighting/scenery considerations. The program has recently been updated to address the question of optimal canopy density and size, and some results from this work are presented below.