Adding expressiveness in musical performance in real time

Musical performance introduces some deviations from nominal values specified in the score. Music reproduced without such variations is usually perceived as mechanical. Most investigations explore how the musical structure influences the performance. There are a few studies on how the musician's expressive intentions are reflected in the performance. The purpose of this work is to develop a model for the expressive modification in real time of musical performance. Perceptual analyses were conducted on some performances played with different intentions (correlated with a set of sensorial adjectives). From these analyses, two distinct expressive directions were observed: the first one correlated with "energy" and the second one with the "kinetics" of the pieces. The two-dimensional space (perceptual Parametric Space, PPS) obtained represents how the subjects arranged the pieces in their own minds. Acoustical analysis allowed us to correlate the expressive directions of the PPS with the main acoustic parameters. Each point of PPS is therefore associated with a set of acoustic parameters. Analysis-by-synthesis method was used to validate the model. In order to carry out computer generated performances, we developed a real time software.