Toward a Rule-based Model for Violin Vibrato

Vibrato is one of the most important expressive parameters that players can control when rendering a piece of music. The simulation of vibrato, in systems for automatic music performance, is still an open problem. A mere regular periodic modulation of pitch generally yields unsatisfactory results, sounding both unnatural and mechanical. An appropriate control of vibrato rate and vibrato extent is a major requirement of a successful vibrato model. The goal of the present work was to develop a generative, rule-based model for expressive violin vibrato. Measurements of vibrato as performed by professional violinists were used for this purpose. The model generates vibrato rate and extent envelopes, which are used to control a sampled violin synthesizer.