The Measurement of Directional Stage Support in a Drama Theatre: Quantifying the Acoustic Effect of a Set

Abstract

The acoustic environment of an auditorium stage can enhance the ability of musicians or actors to hear each other clearly. This is assessed through a set of parameters called 'stage support'. Stage support parameters are conventionally measured using an omnidirectional source and microphone separated by 1 m on the stage. Various stage support parameters are derived from energy ratios of the direct and reflected (or reverberant) sound in the impulse response from source to microphone. The present paper examines the possibility of assessing the directional characteristics of the reflected soundfield by using a multidirectional microphone. Measurements were made in the Sydney Theatre Company's 'Sydney Theatre' with and without a stage set. The microphone used allows first order spherical harmonic decomposition of the soundfield, which was transformed to cardioid components for orthogonal directions (upstage, downstage, left, right, up and down), as well as for horizontal rotations of the cardioid microphone. These were used to calculate directional stage support values. Results demonstrate the potential of this simple extension of standard stage support measurement by showing the acoustical effect of the set.

Chamber musicians' acoustic impressions of auditorium stages: Relation to spatial distribution of early reflections and other parameters

“…This number of factors is far higher than in previous work, where not more than two factors were found from questionnaires with orchestral musicians. 3,4 Besides the use of the more established omnidirectional parameters listed in ISO 3382-1, recent studies have also examined the directionality of on-stage sound fields, 6,7,[18][19][20] including the use of microphone arrays to capture highresolution spatial information. In a series of studies, Ueno et al 18,21,22 developed a method for measuring on-stage auditorium impulse responses using a six-cardioid microphone system (with microphones mutually orientated at 90 ) primarily for real-time, spatially realistic, and measurementbased auralizations of the stage environments in the laboratory.…”

“…In a series of studies, Ueno et al 18,21,22 developed a method for measuring on-stage auditorium impulse responses using a six-cardioid microphone system (with microphones mutually orientated at 90 ) primarily for real-time, spatially realistic, and measurementbased auralizations of the stage environments in the laboratory. Directional versions of stage support measurements were investigated by Cabrera et al 19 using a first-order Ambisonic microphone to demonstrate the spatial acoustic effect of a theatrical stage set. Higher-order Ambisonic microphones are increasingly being used for auditorium acoustics measurements, but mostly without a particular focus on the stage.…”

“…(a) to determine the relationship between existing omnidirectional stage acoustic parameters, and chamber musicians' subjective preferences: In the current paper, as in earlier studies, 3,4,12 the relevance of early reflections on stage (as characterized by EDT on stage, ST Early , G Early ) to musicians is investigated, as well as the relevance of late reflections on stage (as characterized by T 30 , ST Late , and G Late ); (b) to examine ways in which spatial analysis can be used to characterize onstage sound fields and subsequently determine the relationship between these spatiallydefined acoustic parameters, and the subjective preferences of chamber musicians: As noted above, several recent studies have proposed that the spatial distribution of reflection on stage is important. 4,6,7,19 In the current study, the ratio of reflections from above to (i) those from the sides, and (ii) those from the horizontal directions, i.e., sides and back of stage, are considered. Furthermore, the importance of simple architectural ratios of the stage is explored.…”

Variation in Oral-Binaural Room Impulse Responses for Horizontal Rotations of a Head and Torso Simulator

“…In stage acoustics (for example, in drama or opera theatres) sound returned to the actor or singer may provide 'stage support', and perhaps an oralbinaural measurement could quantify this as an alternative to conventional stage support measurements. Stage support measurements are essentially omnidirectional, but the spatial distribution of the early-reflected soundfield on a stage or in a classroom is unlikely to be even [5]. Something of this spatial distribution will be captured by binaural measurement due to the peripheral auditory system's spatial resolving properties.…”