Download Visualization of Signals and Algorithms in Kronos Kronos is a visual-oriented programming language and a compiler aimed at musical signal processing tasks. Its distinctive feature is the support for functional programming idioms like closures and higher order functions in the context of high performance real time DSP. This paper examines the visual aspect of the system. The programming user interface is discussed, along with a scheme for building custom data visualization algorithms inside the system.
Download A New Functional Framework for a Sound System for Realtime Flight Simulation We will show a new sound framework and concept for realistic flight simulation. Dealing with a highly complex network of mechanical systems that act as physical sound sources the main focus is on a fully modular and extensible/scalable design. The prototype we developed is part of a fully functional Full Flight Simulator for Pilot Training.
Download Performing Expressive Rhythms with BillaBoop Voice-Driven Drum Generator In a previous work we presented a system for transcribing spoken rhythms into a symbolic score. Thereafter, the system was extended to process the vocal stream in real-time in order to allow a musician to use it as a voice-driven drum generator. Extensions to this work are the following. First we achieved a study of the system classification accuracy based on typical onomatopoeia used in western beat boxing, with the perspective of building a general supervised model for immediate use. Also, we want the user to be able to generate expressive rhythms, beyond the symbolic drum representation. Thus we considered a class-specific mapping of continuous vocal stream descriptors with either effects or synthesis parameters of the drum generator. The extraction of the symbolic drum stream is implemented in the BillaBoop VST Core plug-in. The class-specific mapping and the sound synthesis are carried out in Plogue Bidule 1 framework. All these components are integrated into a low-latency application that allows its use for live performances.
Download Sonic Screwdrivers: Sound as a Sculptural Process This paper discusses a Fine Art approach to the processes of digital audio. The author puts forward some ideas for a re-defining of digital audio software to embrace a wider audience and to promote the manipulation of sound as a sculptural process removed from, yet still related to, the assumed musical tradition. The authors artworks are introduced, and the impact of current research upon these artworks and upon the authors teaching are discussed.
Download RIR2FDN: An Improved Room Impulse Response Analysis and Synthesis This paper seeks to improve the state-of-the-art in delay-networkbased analysis-synthesis of measured room impulse responses (RIRs). We propose an informed method incorporating improved energy decay estimation and synthesis with an optimized feedback delay network. The performance of the presented method is compared against an end-to-end deep-learning approach. A formal listening test was conducted where participants assessed the similarity of reverberated material across seven distinct RIRs and three different sound sources. The results reveal that the performance of these methods is influenced by both the excitation sounds and the reverberation conditions. Nonetheless, the proposed method consistently demonstrates higher similarity ratings compared to the end-to-end approach across most conditions. However, achieving an indistinguishable synthesis of measured RIRs remains a persistent challenge, underscoring the complexity of this problem. Overall, this work helps improve the sound quality of analysis-based artificial reverberation.
Download FM Parameter Estimation with Low-Order Rational Constraints on Wasserstein Loss Landscape Frequency modulation (FM) synthesis has been widely used in music production and sound design due to its ability to generate rich timbres with few control parameters. However, estimating the frequency parameters from a target sound remains challenging because different parameter configurations can yield similar spectra, creating numerous local minima in the loss landscape. In this paper, we analyze the Wasserstein distance loss landscape for two-operator FM synthesis under practical FFT-based spectral representations and show that it exhibits non-differentiable ridges at rational frequency ratios, arising from negative-frequency folding and spectral ordering transitions. Exploiting this structure, we propose a constrained gradient-based optimization strategy that constrains the frequency ratio in each optimization run to an interval bounded by consecutive low-order rational ratios and retains the lowest-loss candidate across intervals. Experimental results from controlled ablations show that maintaining the constraint throughout optimization improves reliability over random initialization and initialization-only constraints, particularly for more complex spectra at higher modulation indices.
Download Large-scale Real-time Modular Physical Modeling Sound Synthesis Due to recent increases in computational power, physical modeling synthesis is now possible in real time even for relatively complex models. We present here a modular physical modeling instrument design, intended as a construction framework for string- and bar- based instruments, alongside a mechanical network allowing for arbitrary nonlinear interconnection. When multiple nonlinearities are present in a feedback setting, there are two major concerns. One is ensuring numerical stability, which can be approached using an energy-based framework. The other is coping with the computational cost associated with nonlinear solvers—standard iterative methods, such as Newton-Raphson, quickly become a computational bottleneck. Here, such iterative methods are sidestepped using an alternative energy conserving method, allowing for great reduction in computational expense or, alternatively, to real-time performance for very large-scale nonlinear physical modeling synthesis. Simulation and benchmarking results are presented.
Download On studying auditory distance perception in concert halls with multichannel auralizations Virtual acoustics and auralizations have been previously used to study the perceptual properties of concert hall acoustics in a descriptive profiling framework. The results have indicated that the apparent auditory distance to the orchestra might play a crucial role in enhancing the listening experience and the appraisal of hall acoustics. However, it is unknown how the acoustics of the hall influence auditory distance perception in such large spaces. Here, we present one step towards studying auditory distance perception in concert halls with virtual acoustics. The aims of this investigation were to evaluate the feasibility of the auralizations and the system to study perceived distances as well as to obtain first evidence on the effects of hall acoustics and the source materials to distance perception. Auralizations were made from measured spatial impulse responses in two concert halls at 14 and 22 meter distances from the center of a calibrated loudspeaker orchestra on stage. Anechoic source materials included symphonic music and pink noise as well as signals produced by concatenating random segments of anechoic instrument recordings. Forty naive test subjects were blindfolded before entering the listening room, where they verbally reported distances to sound sources in the auralizations. Despite the large variance in distance judgments between the individuals, the reported distances were on average in the same range as the actual distances. The results show significant main effects of halls, distances and signals, but also some unexpected effects associated with the presentation order of the stimuli.
Download Sparse Atomic Modeling of Audio: a Review Research into sparse atomic models has recently intensified in the image and audio processing communities. While other reviews exist, we believe this paper provides a good starting point for the uninitiated reader as it concisely summarizes the state-of-the-art, and presents most of the major topics in an accessible manner. We discuss several approaches to the sparse approximation problem including various greedy algorithms, iteratively re-weighted least squares, iterative shrinkage, and Bayesian methods. We provide pseudo-code for several of the algorithms, and have released software which includes fast dictionaries and reference implementations for many of the algorithms. We discuss the relevance of the different approaches for audio applications, and include numerical comparisons. We also illustrate several audio applications of sparse atomic modeling.
Download Gestural exploitation of ecological information in continuous sonic feedback – The case of balancing a rolling ball Continuous sensory–motor loops form a topic dealt with rather rarely in experiments and applications of ecological auditory perception. Experiments with a tangible audio–visual interface around a physics-based sound synthesis core address this aspect. Initially dealing with the evaluation of a specific work of sound and interaction design, they deliver new arguments and notions for non-speech auditory display and are also to be seen in a wider context of psychoacoustic knowledge and methodology.