Eluding the Influence of Postural Constraints on Cellists’ Bowing Movements and Timbral Quality

Abstract

While playing expressively, cellists tend to produce postural movements, which seem to be part of their musical discourse. This article describes how their instrumental bowing gestures and timbral features of the produced sounds may be affected when constraining these postural (or ancillary) movements. We focus here on a specific acoustic timbre alteration qualified as harshness in the constrained condition. A method based on Canonical Correlation Analysis (CCA) is used to extract the correlations between the bowing displacement and the sound rendition with and without postural constraint among several cellists. Then a detailed investigation of the covariation between gestural and sound data for the duration of the note is carried out, using Functional Data Analysis (FDA) techniques. Results reveal interesting effects of the postural constraint on the coupling patterns between the bowing movement and the spectro-temporal acoustical features.

Cellists’ sound quality is shaped by their primary postural behavior

“…Over the past two decades, we thus observed an increasing interest among the scientific community in better understanding the significance of musicians' corporeal movements related to their expressive sound features. The results revealed the importance of such "ancillary" gestures in supporting or accompanying the instrumentalists' "effective gestures" that are directly responsible for sound production [40][41][42][43][44][45][46] . In particular, investigations of clarinetists' movements have shown that their sense of musical phrasing may be affected during ancillary impairment, i.e., when asked to move as little as possible while keeping their natural expressive intention or when the bell of their instrument was immobilized 47 .…”

The influence of cellist's postural movements on their musical expressivity

“…On en trouve des exemples pour la guitare [Traube 2003], la clarinette [Barthet 2010], le violon [Caclin 2005, Stepanek 2006, Fritz 2012] ou le violoncelle [Rozé 2017a]. Comme préconisé par [Grey 1978, Wessel 1979, Risset 1982, il est préférable de créer un espace de timbre instrumental avec des sons synthétiques calibrés, dont on connaît précisément le contenu spectral et les évolutions harmoniques.…”