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.
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 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 Efficient Modeling and Synthesis of Bell-like Sounds This paper describes two different techniques that can be used to model and synthesize bell-like sounds. The first one is a sourcefilter model based on frequency-zooming ARMA (pole-zero) modeling techniques. The frequency-zooming approach is powerful also in modal analysis of bell sound behavior. The second technique is based on a digital waveguide with a single loop filter that is designed to generate inharmonic partials by including one or more second-order allpass sections in the loop filter, possibly augmented with one or a few parallel resonators. A small handbell with inharmonic partials was recorded and used as a target of modeling and synthesis. Sound examples are found in http://www.acoustics.hut.fi/demos/dafx02/.
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.