Singers show enhanced performance and neural representation of vocal imitation

Humans have a remarkable capacity to finely control the muscles of the larynx, via distinct patterns of cortical topography and innervation that may underpin our sophisticated vocal capabilities compared with non-human primates. Here, we investigated the behavioural and neural correlates of laryngeal control, and their relationship to vocal expertise, using an imitation task that required adjustments of larynx musculature during speech. Highly trained human singers and non-singer control participants modulated voice pitch and vocal tract length (VTL) to mimic auditory speech targets, while undergoing real-time anatomical scans of the vocal tract and functional scans of brain activity. Multivariate analyses of speech acoustics, larynx movements and brain activation data were used to quantify vocal modulation behaviour and to search for neural representations of the two modulated vocal parameters during the preparation and execution of speech. We found that singers showed more accurate task-relevant modulations of speech pitch and VTL (i.e. larynx height, as measured with vocal tract MRI) during speech imitation; this was accompanied by stronger representation of VTL within a region of the right somatosensory cortex. Our findings suggest a common neural basis for enhanced vocal control in speech and song. This article is part of the theme issue ‘Voice modulation: from origin and mechanism to social impact (Part I)’

Singers show enhanced performance and neural representation of vocal imitation

Humans have a remarkable capacity to finely control the muscles of the larynx, via distinct patterns of cortical topography and innervation that may underpin our sophisticated vocal capabilities compared with non-human primates. Here, we investigated the behavioural and neural correlates of laryngeal control, and their relationship to vocal expertise, using an imitation task that required adjustments of larynx musculature during speech. Highly trained human singers and non-singer control participants modulated voice pitch and vocal tract length (VTL) to mimic auditory speech targets, while undergoing real-time anatomical scans of the vocal tract and functional scans of brain activity. Multivariate analyses of speech acoustics, larynx movements and brain activation data were used to quantify vocal modulation behaviour and to search for neural representations of the two modulated vocal parameters during the preparation and execution of speech. We found that singers showed more accurate task-relevant modulations of speech pitch and VTL (i.e. larynx height, as measured with vocal tract MRI) during speech imitation; this was accompanied by stronger representation of VTL within a region of the right somatosensory cortex. Our findings suggest a common neural basis for enhanced vocal control in speech and song. This article is part of the theme issue ‘Voice modulation: from origin and mechanism to social impact (Part I)’

Vocal pedagogy and pedagogical voices

Proceedings of the 9th International Conference on Auditory Display (ICAD), Boston, MA, July 7-9, 2003.Singers learn from their teachers lessons that to the outsider are not transparently obvious. Some of these lessons are discussed in the paper, and their application to problems in sound quality, music information retrieval, and the modeling of the singing voice are presented

Time-Varying Quasi-Closed-Phase Analysis for Accurate Formant Tracking in Speech Signals

In this paper, we propose a new method for the accurate estimation and tracking of formants in speech signals using time-varying quasi-closed-phase (TVQCP) analysis. Conventional formant tracking methods typically adopt a two-stage estimate-and-track strategy wherein an initial set of formant candidates are estimated using short-time analysis (e.g., 10--50 ms), followed by a tracking stage based on dynamic programming or a linear state-space model. One of the main disadvantages of these approaches is that the tracking stage, however good it may be, cannot improve upon the formant estimation accuracy of the first stage. The proposed TVQCP method provides a single-stage formant tracking that combines the estimation and tracking stages into one. TVQCP analysis combines three approaches to improve formant estimation and tracking: (1) it uses temporally weighted quasi-closed-phase analysis to derive closed-phase estimates of the vocal tract with reduced interference from the excitation source, (2) it increases the residual sparsity by using the $L_1$ optimization and (3) it uses time-varying linear prediction analysis over long time windows (e.g., 100--200 ms) to impose a continuity constraint on the vocal tract model and hence on the formant trajectories. Formant tracking experiments with a wide variety of synthetic and natural speech signals show that the proposed TVQCP method performs better than conventional and popular formant tracking tools, such as Wavesurfer and Praat (based on dynamic programming), the KARMA algorithm (based on Kalman filtering), and DeepFormants (based on deep neural networks trained in a supervised manner). Matlab scripts for the proposed method can be found at: https://github.com/njaygowda/ftrac

Models and analysis of vocal emissions for biomedical applications

This book of Proceedings collects the papers presented at the 3rd International Workshop on Models and Analysis of Vocal Emissions for Biomedical Applications, MAVEBA 2003, held 10-12 December 2003, Firenze, Italy. The workshop is organised every two years, and aims to stimulate contacts between specialists active in research and industrial developments, in the area of voice analysis for biomedical applications. The scope of the Workshop includes all aspects of voice modelling and analysis, ranging from fundamental research to all kinds of biomedical applications and related established and advanced technologies

Chanter avec les mains : interfaces chironomiques pour les instruments de musique numériques

This thesis deals with the real-time control of singing voice synthesis by a graphic tablet, based on the digital musical instrument Cantor Digitalis.The relevance of the graphic tablet for the intonation control is first considered, showing that the tablet provides a more precise pitch control than real voice in experimental conditions.To extend the accuracy of control to any situation, a dynamic pitch warping method for intonation correction is developed. It enables to play under the pitch perception limens preserving at the same time the musician's expressivity. Objective and perceptive evaluations validate the method efficiency.The use of new interfaces for musical expression raises the question of the modalities implied in the playing of the instrument. A third study reveals a preponderance of the visual modality over the auditive perception for the intonation control, due to the introduction of visual clues on the tablet surface. Nevertheless, this is compensated by the expressivity allowed by the interface.The writing or drawing ability acquired since early childhood enables a quick acquisition of an expert control of the instrument. An ensemble of gestures dedicated to the control of different vocal effects is suggested.Finally, an intensive practice of the instrument is made through the Chorus Digitalis ensemble, to test and promote our work. An artistic research has been conducted for the choice of the Cantor Digitalis' musical repertoire. Moreover, a visual feedback dedicated to the audience has been developed, extending the perception of the players' pitch and articulation.Le travail de cette thèse porte sur l'étude du contrôle en temps réel de synthèse de voix chantée par une tablette graphique dans le cadre de l'instrument de musique numérique Cantor Digitalis.La pertinence de l'utilisation d'une telle interface pour le contrôle de l'intonation vocale a été traitée en premier lieu, démontrant que la tablette permet un contrôle de la hauteur mélodique plus précis que la voix réelle en situation expérimentale.Pour étendre la justesse du jeu à toutes situations, une méthode de correction dynamique de l'intonation a été développée, permettant de jouer en dessous du seuil de perception de justesse et préservant en même temps l'expressivité du musicien. Des évaluations objective et perceptive ont permis de valider l'efficacité de cette méthode.L'utilisation de nouvelles interfaces pour la musique pose la question des modalités impliquées dans le jeu de l'instrument. Une troisième étude révèle une prépondérance de la perception visuelle sur la perception auditive pour le contrôle de l'intonation, due à l'introduction d'indices visuels sur la surface de la tablette. Néanmoins, celle-ci est compensée par l'important pouvoir expressif de l'interface.En effet, la maîtrise de l'écriture ou du dessin dès l'enfance permet l'acquisition rapide d'un contrôle expert de l'instrument. Pour formaliser ce contrôle, nous proposons une suite de gestes adaptés à différents effets musicaux rencontrés dans la musique vocale. Enfin, une pratique intensive de l'instrument est réalisée au sein de l'ensemble Chorus Digitalis à des fins de test et de diffusion. Un travail de recherche artistique est conduit tant dans la mise en scène que dans le choix du répertoire musical à associer à l'instrument. De plus, un retour visuel dédié au public a été développé, afin d'aider à la compréhension du maniement de l'instrument

Vocal imitation for query by vocalisation

PhD ThesisThe human voice presents a rich and powerful medium for expressing sonic ideas such as musical sounds. This capability extends beyond the sounds used in speech, evidenced for example in the art form of beatboxing, and recent studies highlighting the utility of vocal imitation for communicating sonic concepts. Meanwhile, the advance of digital audio has resulted in huge libraries of sounds at the disposal of music producers and sound designers. This presents a compelling search problem: with larger search spaces, the task of navigating sound libraries has become increasingly difficult. The versatility and expressive nature of the voice provides a seemingly ideal medium for querying sound libraries, raising the question of how well humans are able to vocally imitate musical sounds, and how we might use the voice as a tool for search. In this thesis we address these questions by investigating the ability of musicians to vocalise synthesised and percussive sounds, and evaluate the suitability of different audio features for predicting the perceptual similarity between vocal imitations and imitated sounds. In the first experiment, musicians were tasked with imitating synthesised sounds with one or two time–varying feature envelopes applied. The results show that participants were able to imitate pitch, loudness, and spectral centroid features accurately, and that imitation accuracy was generally preserved when the imitated stimuli combined two, non-necessarily congruent features. This demonstrates the viability of using the voice as a natural means of expressing time series of two features simultaneously. The second experiment consisted of two parts. In a vocal production task, musicians were asked to imitate drum sounds. Listeners were then asked to rate the similarity between the imitations and sounds from the same category (e.g. kick, snare etc.). The results show that drum sounds received the highest similarity ratings when rated against their imitations (as opposed to imitations of another sound), and overall more than half the imitated sounds were correctly identified with above chance accuracy from the imitations, although this varied considerably between drum categories. The findings from the vocal imitation experiments highlight the capacity of musicians to vocally imitate musical sounds, and some limitations of non– verbal vocal expression. Finally, we investigated the performance of different audio features as predictors of perceptual similarity between the imitations and imitated sounds from the second experiment. We show that features learned using convolutional auto–encoders outperform a number of popular heuristic features for this task, and that preservation of temporal information is more important than spectral resolution for differentiating between the vocal imitations and same–category drum sounds