Seminar by Esteban Maestre on sound synthesis

Seminar by Esteban Maestre on sound synthesis

Monday, May 7th, at 15:30h in room 55.309 (Universitat Pompeu Fabra)



Esteban Maestre, McGill University (Canada)  - web

Efficient sound synthesis by recursive digital filters in parallel form: virtual musical instruments and artificial reverberation

Recursive digital filters in parallel form offer a number of advantages. Besides their suitability for parallel implementation, improved numerical precision and parametric control are some of their attractive features. This talk will cover some recent progress in using frequency-domain optimization techniques to design high-order recursive parallel filters suited for the efficient simulation musical instruments and reverberation via modal synthesis.  

The presentation will first introduce novel methods to render musical instrument sound by combining the digital waveguide and modal synthesis frameworks. Through a modal analysis technique based on constrained optimization of parallel filter coefficients, measured resonator immitances are faithfully reproduced via an efficient modal formulation that allows their realization as lumped elements within a digital waveguide model. Sound examples will be provided for wind and string instruments.

Then, the problem of designing a modal reverberator to match a measured room impulse response will be considered. The modal reverberator architecture expresses a room impulse response as a parallel combination of resonant filters, with the pole locations determined by the room resonances and decay rates, and the zeros by the source and listener positions. The method first estimates the pole positions in an iterative process involving a series of constrained pole position optimizations in overlapping frequency bands. With the pole locations in hand, the zeros are fit to the measured impulse response using least squares. Example models for a medium sized room will be provided.