Download Modeling Interactions between Rubbed Dry Surfaces Using an Elasto-Plastic Friction Model A physically based model of the frictional interaction between dry surfaces is presented. The paper reviews a number of static and dynamic friction models, and discusses numerical techniques for the accurate and efficient numerical implementation of a dynamic elasto-plastic model. An application to the bowed string is provided, and the resulting simulations are compared to recent results from the literature.
Download Modeling Bowl Resonators Using Circular Waveguide Networks We propose efficient implementations of a glass harmonica and a Tibetan bowl using circular digital waveguide networks. Circular networks provide a physically meaningful representation of bowl resonators. Just like the real instruments, both models can be either struck or rubbed using a hard mallet, a violin bow, or a wet finger.
Download Real-Time Spatial Processing and Transformations of a Singing Bowl We propose different real-time spatial-modal manipulations of a physical model of a singing bowl. The high number of degrees of freedom in the model, combined with spatial processing algorithms, provides the possibility of obtaining rich and expressive transformations.
Download Inharmonic Sound Spectral Modeling by Means of Fractal Additive Synthesis In previous editions of the DAFX [1, 2] we presented a method for the analysis and the resynthesis of voiced sounds, i.e., of sounds with well defined pitch and harmonic-peak spectra. In a following paper [3] we called the method Fractal Additive Synthesis (FAS). The main point of the FAS is to provide two different models for representing the deterministic and the stochastic components of voiced-sounds, respectively. This allows one to represent and reproduce voiced-sounds without loosing the noisy components and stochastic elements present in real-life sounds. These components are important in order to perceive a synthetic sound as a natural one. The topic of this paper is the extension of the technique to inharmonic sounds. We can apply the method to sounds produced by percussion instruments as gongs, tympani or tubular bells, as well as to sounds with expanded quasi-harmonic spectrum as piano sounds.
Download Spatio-Operational Spectral (S.O.S.) Synthesis We propose an approach to digital audio effects using recombinant spatialization for signal processing. This technique, which we call Spatio-Operational Spectral Synthesis (SOS), relies on recent theories of auditory perception. The perceptual spatial phenomenon of objecthood is explored as an expressive musical tool.
Download EDS Parametric Modeling and Tracking of Audio Signals Despite the success of parametric modeling in various fields of digital signal processing, the Fourier analysis remains a prominent tool for many audio applications. This paper aims at demonstrating the usefulness of the Exponentially Damped Sinusoidal (EDS) model both for analysis/synthesis and tracking purposes.
Download Iterative Method for Harmonic and Exponentially Damped Sinusoidal Models We present two evolutions of the well known Exponentially Damped Sinusoidal model, named HDS (Harmonic Exponentially Damped Sinusoidal) model for single pitch signals and HDSM for multi-pitch signals modeling. Additionally, we propose to use an iterative high-accuracy algorithm to estimate the model parameters. Compared with full or fast implementations of highresolution methods (Matrix Pencil, ESPRIT, Kung’s algorithm, ...), this approach has a lower computational complexity and is well adapted to the Harmonic Damped Sinusoidal models since it takes into account the harmonic relations between the angularfrequencies. In the context of low bit-rate audio coding, we show the validity of this approach on several audio signals.
Download Real-Time Noise Synthesis with Control of the Spectral Density We propose in this paper a spectral synthesis model to generate noisy sounds with independent control parameters for spectral density and spectral envelope. Algorithms defining in a efficient way these spectral properties from the statistical parameters of the model are presented in details. Real-time implementation is composed of many methods which can be sequenced.
Download Physical Constraints for the Control of a Physical Model of a Trumpet In this paper, the control of a physical model of a trumpet is studied. Although this model clearly describes the mechanical and acoustical phenomena that are perceptually relevant, additional constraints must be imposed on the control parameters. In contrast with the model where the tube length can be varied continuously, only seven different tube lengths can be obtained with a real instrument. By studying the physical model and its implementation, different relationships between the control parameters and signal characteristics are identified. These relationships are then used to obtain the best set of tube lengths with respect to a given tuning frequency.
Download Digital Waveguide Mesh Modeling of Room Acoustics: Improved Anechoic Boundaries Digital waveguide mesh structures have proved useful in a wide variety of modelling applications. When modelling the acoustics of an enclosed space the accurate simulation of specific boundary conditions is paramount but waveguide mesh related techniques have as yet to provide an appropriate and reliable solution. This paper gives an overview of boundary types that have been implemented by researchers to date and describes the application of a higher order approximation for the particular case of an anechoic boundary, that may prove useful as part of a more general solution.