Vincent Fréour

Acoustical interaction between vibrating lips, downstream air column, and upstream airways in trombone performance

This paper presents experimental results on the acoustical influence of the vocal tract in trombone performance. The experimental approach makes use of measurements at the interface between the player and instrument, allowing a relative comparison between upstream airways and the downstream air column impedances, as well as an estimation of the phase of the impedance of the upstream and downstream systems. Measurements were conducted over the full traditional range of playing, during sustained tones with varying dynamic, as well as in special effects such as pitch bending. Subjects able to play over the full range demonstrated significant upstream influence in the higher register of the instrument. These players were categorized in two groups according to their ability to control the phase of the upstream impedance and their ability to generate powerful downstream acoustic energy. Sustained tones played with varying dynamics showed a general tendency of a decrease in vocal-tract support with increase in loudness. Although pitch bends did not involve significant upstream influence at f0, results suggest modification of the lip behavior during bending. Vocal-tract tuning at tone transitions was also investigated and found to potentially contribute to slur articulations.

On gestural variation and coarticulation effects in sound control

In this paper we focus on the analysis of sound producing gestures in the musical domain. We investigate the behavior of intraoral pressure exerted by a trumpet performer in the production of single and concatenated notes. Investigation is carried out with functional data analysis techniques. Results show that different variation patterns occur for single note production, which depend on dynamic level, suggesting the hypothesis that two different motor control programs are available. Results from analysis on consecutive notes give evidence that the coarticulation between two gesture curves cannot be modelled by linear superposition, and that local coarticulation is affected by contiguous units.

Measures of Facial Muscle Activation, Intra-oral Pressure and Mouthpiece Force in Trumpet Playing

Abstract Trumpet performance builds on the synergy of multiple factors. From a physiological point of view, the production of a simple musical tone relies on the control of the pressure at the lips, the contact force on the mouthpiece, and the oral articulatory gestures and configurations. Whereas previous studies described the magnitude of these control parameters in the quasi-static regime of the oscillation, the present investigation focuses on their temporal evolution and interrelation. Intra-oral pressure, mouthpiece force, facial muscular activity of two groups of muscles, and the radiated sound were recorded from three professional players performing isolated and articulated tones with three different dynamics. Results showed that the experimental conditions affected the amount and location of variability in the performance, and the behaviour of intra-oral pressure at note initiation. All together, this suggests that different dynamics and sequencing may cause a reorganization of the mechanisms underlying the production of a tone.

Extraction and analysis of body-induced partials of guitar tones

Guitar plucked sounds arise from a rapid input of energy applied to the string coupled to the instrument body at the bridge. For the radiated pressure, this results in quasi-harmonic contributions, reflecting the string modes coupled to the body, as well as some transient and quickly decaying components reflecting the excitation of the body modes of the instrument. In order to evaluate the relevance of this transient body sound, a high resolution analysis-synthesis method is described for the extraction of the body-mode contribution from the radiated pressure measured in the near field of the guitar top plate. This analysis scheme is first tested on synthesized signals. Some body-sound emergence indicators are then proposed and computed over a pool of instruments. The influence of the conditions of excitation on the body-sound emergence is investigated, and the instruments categorized according to these objective descriptors. Results show a larger range of body-sound emergence with variations of the plucking position in hand-made guitars compared to industrial instruments. This suggests that these particular hand-made instruments are more sensitive to variations in the control from the player and hence allow a wider range of timbres with respect to the transient coloration of the body modes.

Synchronous Multimodal Measurements on Lips and Glottis: Comparison Between Two Human-Valve Oscillating Systems

HAL is a multi-disciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L’archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d’enseignement et de recherche français ou étrangers, des laboratoires publics ou privés. Synchronous Multimodal Measurements on Lips and Glottis: Comparison Between Two Human-Valve Oscillating Systems Thomas Hézard, Vincent Fréour, René Caussé, Thomas Hélie, Gary P. Scavone

Simulating different upstream coupling conditions on an artificial trombone player system using an active sound control approach

Recent research suggests that the ability to finely tune vocal-tract resonances during trombone playing may constitute an important aspect of performance expertise. Artificial player systems, designed to reproduce the behaviour of a real player, often neglect this component by not providing any control of upstream resonances. However, they offer great experimental platforms for quantitative studies on sound production mechanisms, allowing independent adjustment of certain control parameters. An active sound control method was designed to improve high tone support and investigate different conditions of coupling between the artificial lips, the downstream air-column and the upstream cavity during sustained tones played by an artificial valve-trombone player system. Upstream input impedance at the fundamental frequency was controlled through real-time adjustment of the phase and amplitude ratio between the acoustic pressure generated on both sides of the lips. The phase difference between the upstream and d...

Numerical investigation on the influence of wall vibrations on the behavior of the lip excitation in brass instruments

The influence of wall vibrations in brass instruments has been an object of substantial debate in both musician and scientific communities. The excitation of the instrument wall (from the acoustic field inside the instrument and through the direct mechanical excitation from the lips) may influence the acoustic pressure field inside and outside the instrument, potentially resulting into some noticeable effects on the acoustic input impedance and radiated sound. These effects have been the object of numerical and experimental studies on different families of wind instruments. Furthermore, these vibrations are also likely to induce some perturbations on the excitation mechanism itself (the lips of the player), that may contribute to variations of the produced tone, as well as influence the sensations of the player. In this paper, the effects of the this mechanical coupling between the lips and vibrating wall is studied numerically using a physical model of the lips, coupled acoustically to the air-column of ...

Evaluation of two control parameters of trumpet players as function of sound features.

Experiments were performed by five trumpet players with the same trumpet and mouthpiece. For each subject, two control parameters are measured: mouth-pressure and force applied by the lips on the mouthpiece. The sound is also recorded. The players are asked to play sustained notes at different pitch and sound levels. We calculate fundamental frequency, sound pressure level, and some spectral features: noisiness, spectral roll-off, etc. Although little mouth-pressure variability as function of pitch and dynamic appears between subjects, clear differences were obtained in terms of the force applied on the mouthpiece. Therefore, we suggest to focus on the link between sound features and the ratio of these two control parameters measured, sort of “gesture estimator.” The representation of the ratio as function of the sound features shows a good classification of musicians. Moreover, in some specific cases such as noisiness, the relation seems independent from the players. These observations suggest that these two control parameters could be efficient to characterize players’ embouchure and to access some sound characteristics without knowledge of the mechanical characteristics of the lips. These results will be described and discussed, and direction for future works suggested. [Consonnes project, supported by the French Research Agency].

Study of brass performer gestures

Brass instrument playing requires the musican to control his respiratory gesture and the elastic properties of his lips. This raises the question of musician gesture optimisation and strategy in order to complete a musical exercise. It also makes gesture characterization very hard to conduct in a non-invasive way. On the other hand, it is possible to measure some control parameters (linked to the respiratory and lip-adjustment gesture) like lip force applied on the mouthpiece and mouth air pressure. Theses parameters measurements and also the specific mouthpiece receiver developed to measure lip force with a minimum interference to the player are presented. Respiratory flows during live playing are also evaluated thanks to the calibration of respiratory belts used on the thoracial and abdominal regions of musicians. Details of the method for carrying out this type of measurement and preliminary results are reported. During this measurement sound recording and analysis are also conducted thanks to a set of audio descriptors. Links between control parameters measurements and sound characterisation are examined. Parallel development of a automated artificial mouth, used for experimental validations, is also outlined. [Work, within the CONSONNES project, is lead with the support of the French Research National Agency ANR].