Performance Expression in Commuted Waveguide Synthesis of Bowed Strings
David A. Jaffe, Julius O. Smith · 1995
ABSTRACT: In [Smith 1993], an approach was described for implementing efficient real-time bowed string synthesis. Recent work has focused on differentiating the members of the violin family, as well as on the flexibility necessary to create expressive performance. This paper presents a technique for creating smooth transitions between notes, enabling a variety of bowing styles to be synthesized, such as legato, marcato and martele. A method for supporting such left-hand techniques as vibrato and glissando is also given, as is the efficient simulation of pitch-correlated bow noise. Examples from various periods of music history have been convincingly synthesized in real time using the Music Kit and DSP56001 under NEXTSTEP. 1. Motivation—Better Bowed and Plucked String Instruments The current de facto standard in string synthesis is a MIDI keyboard controlling a sampler. There are two main problems with this approach. First, the keyboard model is inadequate to represent the continuity possible with stringed instruments. Second, sampling is notoriously inflexible when it comes to expression and nuance. 1.1 Efficient Physical Models Physical modeling side-steps the problems of sampling by beginning, not with an acoustic waveform,