Fundamental to both performance and experience of rhythm in music is a connection between musical rhythm and patterns of body movements. Through this connection body movements are given a rhythmic form, and rhythm in music is related to ordered movements of the body.
A main focus in this study is to investigate possible relations between movement categories and rhythmic expression. An analytical approach to this task is to regard a musicianís various ways of moving when playing an instrument as an expression of timbral aspects of rhythm, and to apply FFT to empirical data of the musicianís movements in order to detect spectral components that are characteristic of the performance. This approach is exemplified in an empirical investigation of various jazz drummersí movements in performances of swing grooves. We have constructed a series of experiments where the drummers are asked to play swing grooves related to various performance parameters (tempo: ranging from 60 beats pr. minute to 300 bpm; accents: play different versions of swing groove with accents on different notes in the swing pattern; swing ratio: play swing grooves applying different rhythmic subdivisions of the beat). Kinematic as well as dynamic aspects of the performances are measured and analyzed, and spectral characteristics related to differences in tempo, accents and rhythmic phrasing are studied.
This spectral approach to rhythm performance might also suggest alternative ways of constructing syntheses and models of rhythm production.