Download Nonlinear modeling of a guitar loudspeaker cabinet
Distortion is a desirable effect for sound coloration in electric guitar amplifiers and effect processors. At high sound levels, particularly at low frequencies, the loudspeakers used in classic style cabinets are also a source of distortion. This paper presents a case study of measurements and digital modeling of a typical guitar loudspeaker as a real-time audio effect. It demonstrates the complexity of the driver behavior, which cannot be efficiently modeled in true physical detail. A model with linear transfer functions and static nonlinearity characteristics to approximate the measured behavior is derived based upon physical arguments. An efficient method to simulate radiation directivity is also proposed.
Download Simulation of piano sustain-pedal effect by parallel second-order filters
This paper presents a sustain-pedal effect simulation algorithm for piano synthesis, by using parallel second-order filters. A robust two-step filter design procedure, based on frequency-zooming ARMA modeling and least squares fit, is applied to calibrate the algorithm from impulse responses of the soundboard and the string register. The model takes into account the differences in coupling between the various strings. The algorithm can be applied to both sample-based and physics-based piano synthesizers.