Digital modeling of bridge driving-point admittance from measurements on violin-family instruments

Abstract

We present a methodology for digital modeling of D-dimensional driving-point bridge admittances from vibration measurements on instruments of the violin family. Our study, centered around the two-dimensional case for violin, viola, and cello, is based on using the modal framework to construct an admittance formulation providing physically meaningful and effective control over model parameters. In a first stage, mode frequencies and bandwidths are estimated in the frequency domain via solving a non-convex, constrained optimization problem. Then, mode amplitudes are estimated via semidefinite programming while enforcing passivity. We obtain accurate, low-order digital admittance models suited for real-time sound synthesis via physical models.