Analysis and synthesis of expressive intentions in musical performance

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 analyze, both from a perceptual and sonological point of view, how the performance of a score differs when the musicians are requested to play it with different expressive characters. Professional musicians were asked to play short pieces of music in different versions, namely, so that it sounds light, heavy, soft, hard, bright, and dark. For comparison a normal, standard performance was recorded. By analyzing the results of perceptual analysis, two quite distinct expressive directions were observed, one tending towards brightness and the other, towards softness of the pieces. The two dimensional space so obtained represents a model of expressivity, by which the subjects arranged the pieces in their own minds. Sonological analysis allowed us to identify the variations of the main sonological parameters on varying the expressive intentions. It was possible to identify two distinct expressive sources. The first refers the musical structure of the period, its division into phrases and the continuous alternation of tension and relaxation points. The second depends on the expressive intentions intentions that the musician wants to convey to the listeners.