On the Adaptation of the Linear Bicharacteristic Scheme to Block-Based Physical Modeling for Digital Sound Synthesis of String Instruments

Block-based physical modeling is one of the most promising methods for digital sound synthesis. This technique proposes to model and discretize each instrument element separately and then, to implement their interaction. In this paper, the use of the linear bicharacteristic scheme (LBS) or upwind leapfrog is proposed for digital sound synthesis of string instruments. It provides an efficient and accurate alternative stencil to the classical leapfrog scheme of the finite difference time domain (FDTD) method. Moreover, the conversion of dependent wave equation variables into characteristic variables makes this method suitable to interact with wave digital filter models and others paradigms. This technique is extensively presented and finally justified with some examples