Tempo and Loudness Analysis of a Continuous 28-Hour Performance of Erik Satie’s Composition “Vexations”

Abstract

This study extends the perspective of music performance research with an examination of a long-term performance. In a single case study, an uninterrupted recording of Erik Satie’s “Vexations” performed by one pianist over almost 28 hours is used as a performance of extreme length to explore new approaches in performance data analysis. The MIDI and acoustical data are analysed with linear and non-linear methods to describe changes in tempo and loudness. Additionally, the performer’s changing states of consciousness (alertness, trance, drowsiness) were observed to exert a strong influence on tempo and loudness stability. Tempo and loudness remain stable over the first 14 hours of alertness. A state of trance begins after 15 hours and shows a destabilisation of tempo followed by uncontrolled deviations in loudness. Time series analysis of loudness changes revealed periodicities of about 10 minute lengths. Non-linear analyses of tempo and loudness changes showed a complex generator pattern underlying the apparently random fluctuations throughout the performance. This pattern appears most clearly when unfolded in an 18-dimensional embedding space. Measures of fractality and chaotic behavior proved to be dependent on the states of consciousness. Results are discussed in regard to influences of psycho-physiological changes (vigilance) on sensorimotor performance and to the overall stability of an oscillating psycho-motoric system.