Kosuke Kato

Effect of room acoustics on musicians' performance. part I: Experimental investigation with a conceptual model

This study aimed to investigate the notion that musicians adjust their performance to suit the acoustics of concert halls. First, a schematic model was developed to provide a basis for the investigation. Second, a performance experiment was conducted: musicians performed under different acoustic conditions simulated in an anechoic room. The performances were recorded, and the musicians were interviewed about the technical details of the adjustments that they made to suit the acoustics. The results showed how expert musicians adapted their performances to the acoustics. Third, as a pilot study to examine if differences could be objectively identified, a listening test and acoustic analysis were conducted on a recorded violin performance. The study confirmed that differences could indeed be objectively identified, at least in terms of the tempo and extent of vibrato.

Blending vocal music with a given sound field due to the characteristics of the running autocorrelation function of singing voices

This is a study to meet music and the opera house acoustics. It is said that singers adjust their interpretation style according to the acoustical condition of the sound field in a room. However, this mechanism of blending of musical performance with the sound field is unknown. In order to obtain a method of performance blending of opera house acoustics, we attempted to develop evaluation criteria for a singing voice in terms of the minimum value of the effective duration of the running autocorrelation function (r‐ACF), (te)min, of sound source signals. This temporal factor has shown to have close correlation with the subjective response of both listeners and performers to sound fields [Y. Ando, Architectural Acoustics (AIP Press/Springer‐Verlag, New York, 1998)]. As example for the control of (te)min due to performing style, effects of singing style, kind of vowel, relative pitch, vibrato extent, and intonation on the values of (te)min are demonstrated. In addition, the fine structure of the r‐ACF is dis...

Singer’s preferred acoustic condition in performance in an opera house and self‐perception of the singer’s voice

Solo singers have been shown to over estimate the relative sound pressure level of a delayed, external reproduction of their own voice, singing single syllables, which, in turn, appears to influence the preferred delay of simulated stage reflections [Noson, Ph.D. thesis, Kobe University, 2003]. Bone conduction is thought to be one factor separating singer versus instrumental performer judgments of stage acoustics. Using a parameter derived from the vocal signal autocorrelation function (ACF envelope), the changes in singer preference for delayed reflections is primarily explained by the ACF parameter, rather than internal bone conduction. An auditory model of a singer’s preferred reflection delay is proposed, combining the effects of acoustical environment (reflection amplitude), bone conduction, and performer vocal overestimate, which may be applied to the acoustic design of reflecting elements in both upstage and forestage environments of opera stages. For example, soloists who characteristically undere...