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 Creating Music by Means of ´Physical Thinking`: The Musician Oriented Genesis Environment Mass-interaction physical modeling scheme is often cited as the traditional physical modeling technique, but surprisingly some of the possibilities for musical creation it allows have not yet been pointed out. GENESIS is a graphical environment based on the CORDIS-ANIMA mass-interaction paradigm and designed for musicians. It was conceived so as to help the user "think physical"; that is, to discover and experiment with new ways of creating music, which is necessary when using physical modeling. The paper introduces version 1.5 of the GENESIS environment. Its major features and ergonomic aspects are exposed – especially model representation, low and high level modeling tools, multisensorial simulation facilities. Examples of composer's works are presented.
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 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 On the Nonlinear Commuted Synthesis of the Piano In this paper a novel method is presented for the physics-based sound synthesis of the piano, based on digital waveguides. The approach combines the advantages of the commuted synthesis technique and the methods using a nonlinear hammer model. The interaction force of the hammer-string contact is computed by an auxiliary digital waveguide connected to a nonlinear hammer model. This force signal is used as a target impulse response for designing a low-order digital filter real-time. The piano sound is calculated by filtering the soundboard response with the hammer filter and feeding this signal to a synthesizer digital waveguide. A new method is presented for separating the contribution of the interaction force and the soundboard in measured piano tones. For modeling beating, a new technique is proposed based on a simplified pitch-shift effect. Considerations on modeling the effect of sustain pedal are also given. It is shown that the technique of designing the hammer filter real-time is not only useful for digital waveguide modeling, but it can be combined with sampling synthesis too.
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 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.
Download Gestural Strategies for Specific Filtering Processes The gestural control of filters implies the definition of these filters and the way to activate them with gesture. We give here the example of several real “virtual instruments” which rely on this gestural control. This way we show that music making is different from algorithm producing and that a good gestural control may substitute to, or at least complement, a complex scheme using digital audio effects in real time implementations [1].
Download Recognition of Distance Cues from a Virtual Spatialization Model Emerging issues in the auditory display aim at increasing the usability of interfaces. In this paper we present a virtual resonating environment, which synthesizes distance cues by means of reverberation. We realize a model that recreates the acoustics inside a tube, applying a numerical scheme called Waveguide Mesh, and we present the psychophysical experiments we have conducted for validating the information about distance conveyed by the virtual environment.