The role of diffusive architectural surfaces on auditory spatial discrimination in performance venues

Abstract

In musical or theatrical performance, some venues allow listeners to individually localize and segregate individual performers, while others produce a well blended ensemble sound. The room acoustic conditions that make this possible, and the psycho-acoustic effects at work are not fully understood. This research utilizes auralizations from measured and simulated performance venues to investigate spatial discrimination of multiple acoustic sources in rooms. Signals were generated from measurements taken in a small theater, and listeners in the audience area were asked to distinguish pairs of speech sources on stage with various spatial separations. This experiment was repeated with the proscenium splay walls treated to be flat, diffusive, or absorptive. Similar experiments were conducted in a simulated hall, utilizing 11 early reflections with various characteristics, and measured late reverberation. The experiments reveal that discriminating the lateral arrangement of two sources is possible at narrower separation angles when reflections come from flat or absorptive rather than diffusive surfaces.

Effects of the Distance from a Diffusive Surface on the Objective and Perceptual Evaluation of the Sound Field in a Small Simulated Variable-Acoustics Hall

“…The values of this parameter at the positions close to the lateral wall were different for the DM and DF conditions. Robinson et al [64] showed that the correlation between the impulse responses at two ears at positions close to any surface is lower due to effects of the surface proximity on the impulse response of the ear oriented towards it. In this way, the binaural impulse response is affected asymmetrically on each ear channel (left and right).…”

The sound diffusion in Italian Opera Houses: Some examples

“…We could extend this result stating that in Italian-style opera houses, there are very often problems of focalization of the sound field especially in the stalls and in the boxes (mainly in the first order) Moreover, several authors found that diffusion and scattering in Opera Houses represent a fundamental issue, [18][19][20] to be measured [21][22][23] or simulated. 24,25 This phenomenon leads to design special devices, as diffusing panels, that could be inserted in the theatres, to avoid focalization and improve the acoustic quality.…”

Architectural Features That Make Music Bloom in Concert Halls

“…It reduces the phase coherence of sound signals that might reduce the clarity and the quality of bass [31]. Moreover, a reflection from a scattering surface makes the localization worse than a reflection from a flat or absorptive wall [32]. Scattering elements, in many modern cases, are on a similar scale throughout the hall, resulting in the attenuation of only certain frequencies.…”