Download Generation of Non-repetitive Everyday Impact Sounds for Interactive Applications The use of high quality sound effects is growing rapidly in multimedia, interactive and virtual reality applications. The common source of audio events in these applications is impact sounds. The sound effects in such environments can be pre-recorded or synthesized in real-time as a result of a physical event. However, one of the biggest problems when using pre-recorded sound effects is the monotonous repetition of these sounds which can be tedious to the listener. In this paper, we present a new algorithm which generates non-repetitive impact sound effects using parameters from the physical interaction. Our approach aims to use audio grains to create finely-controlled synthesized sounds which are based on recordings of impact sounds. The proposed algorithm can also be used in a large set of audio data analysis, representation, and compression applications. A subjective test was carried out to evaluate the perceptual quality of the synthesized sounds.
Download A Parametric Model of Piano Tuning A parametric model of aural tuning of acoustic pianos is presented in this paper. From a few parameters, a whole tessitura model is obtained, that can be applied to any kind of pianos. Because the tuning of piano is strongly linked to the inharmonicity of its strings, a 2-parameter model for the inharmonicity coefficient along the keyboard is introduced. Constrained by piano string design considerations, its estimation requires only a few notes in the bass range. Then, from tuning rules, we propose a 4-parameter model for the fundamental frequency evolution on the whole tessitura, taking into account the model of the inhamonicity coefficient. The global model is applied to 5 different pianos (4 grand pianos and
Download Nonlinear Allpass Ladder Filters in FAUST Passive nonlinear filters provide a rich source of evolving spectra for sound synthesis. This paper describes a nonlinear allpass filter of arbitrary order based on the normalized ladder filter. It is expressed in FAUST recursively in only two statements. Toward the synthesis of cymbals and gongs, it was used to make nonlinear waveguide meshes and feedback-delay-network reverberators.
Download A Preliminary Study on Sound Delivery Methods for Footstep Sounds In this paper, we describe a sound delivery method for footstep sounds, investigating whether subjects prefer static rendering versus dynamic. In this case, dynamic means that the sound delivery method simulates footsteps following the subject. An experiment was run in order to assess subjects’ preferences regarding the sound delivery methods. Results show that static rendering is not significantly preferred to dynamic rendering, but subjects disliked rendering where footstep sounds followed a trajectory different from the one they were walking along.
Download Mapping blowing pressure and sound features in recorder playing This paper presents a data-driven approach to the construction of mapping models relating sound features and blowing pressure in recorder playing. Blowing pressure and sound feature data are synchronously obtained from real performance: blowing pressure is measured by means of a piezoelectric transducer inserted into the mouth piece of a modified recorder, while produced sound is acquired using a close-field microphone. Acquired sound is analyzed frame-by-frame, and features are extracted so that original sound can be reconstructed with enough fidelity. A multi-modal database of aligned blowing pressure and sound feature signals is constructed from real performance recordings designed to cover basic performance contexts. Out of the gathered data, two types of mapping models are constructed using artificial neural networks: (i) a model able to generate sound feature signals from blowing pressure signals, and therefore used to produce synthetic sound from recorded blowing pressure profiles via additive synthesis; and (ii) a model able to estimate the blowing pressure from extracted sound features.
Download A Csound Opcode for a Triode Stage of a Vacuum Tube Amplifier The Csound audio programming language adheres to the inputoutput paradigm and provides a large number of specialized commands (called opcodes) for processing output signals from input signals. Therefore it is not directly suitable for component modeling of analog circuitry. This contribution describes an attempt to virtual analog modeling and presents a Csound opcode for a triode stage of a vacuum tube amplifier. Externally it communicates with other opcodes via input and output signals at the sample rate. Internally it uses an established wave digital filter model of a standard triode. The opcode is available as library module.
Download The Image-Source Reverberation Model in an N-Dimensional Space The image method is generalized to geometries with an arbitrary number of spatial dimensions. n-dimensional (n-D) acoustics is discussed, and an algorithm for n-D room impulse response calculations is presented. Synthesized room impulse responses (RIRs) from n-D rooms are presented. RIR characteristics are discussed, and computational considerations are examined.
Download Transforming Vibrato Extend in Monophonic Sounds This paper describes research into signal transformation operators allowing to modify the vibrato extent in recorded sound signals. A number of operators are proposed that deal with the problem taking into account different levels of complexity. The experimental validation shows that the operators are effective in removing existing vibrato in real world recordings at least for the idealized case of long notes and with properly segmented vibrato sections. It shows as well that for instruments with significant noise level (flute) independent treatment of noise and harmonic signal components is required.
Download FAUST Architectures Design and OSC Support FAUST [Functional Audio Stream] is a functional programming language specifically designed for real-time signal processing and synthesis. It consists in a compiler that translates a FAUST program into an equivalent C++ program, taking care of generating the most efficient code. The FAUST environment also includes various architecture files, providing the glue between the FAUST C++ output and the host audio and GUI environments. The combination of architecture files and FAUST output gives ready to run applications or plugins for various systems, which makes a single FAUST specification available on different platforms and environments without additional cost. This article presents the overall design of the architecture files and gives more details on the recent OSC architecture.
Download Time-Variant Delay Effects based on Recurrence Plots Recurrence plots (RPs) are two-dimensional binary matrices used to represent patterns of recurrence in time series data, and are typically used to analyze the behavior of non-linear dynamical systems. In this paper, we propose a method for the generation of time-variant delay effects in which the recurrences in an RP are used to restructure an audio buffer. We describe offline and realtime systems based on this method, and a realtime implementation for the Max/MSP environment in which the user creates an RP graphically. In addition, we discuss the use of gestural data to generate an RP, suggesting a potential extension to the system. The graphical and gestural interfaces can provide an intuitive and convenient way to control a time varying delay.