The influence of the bow on aperiodicity of violin notes
Robert T. Schumacher · The Journal of the Acoustical Society of America · 1991
A method has been demonstrated to investigate the aperiodicity in nearly periodic signals [R. T. Schumacher and C. Chafe, ICASSP-90, Paper 6.A1.18, Albuquerque, NM (1990)]. This method, the norm difference method, quantifies the fluctuations in the shapes of waveforms from cycle to cycle. The norm difference method will be explained. As an application, a study of the difference in aperiodicity of a note separately played on a violin by two bows will be presented. In addition, a brief survey of the range of aperiodicities exhibited by other orchestral instruments will be presented in order to compare them with characteristic bowed string aperiodicities.