The technique of �open throat� is a pedagogical concept transmitted through the oral tradition of singing. This thesis explored the pedagogical perceptions and practices of �open throat� using empirical methodologies to assess technical skill and associated vocal quality. In the first study (Mitchell, Kenny, Ryan, & Davis, 2003), we assessed the degree of consensus amongst singing pedagogues regarding the definition of, and use in the singing studio of the technique called �open throat.� Results indicated that all fifteen pedagogues described �open throat� technique as fundamental to singing training and were positive about the sound quality it achieved, especially in classical singing. It was described as a way of maximising pharyngeal space or abducting the false vocal folds. Hypotheses generated from pedagogical beliefs expressed in this first study were then tested acoustically (Mitchell & Kenny, 2004a, 2004b). Six advanced singing students sang in two conditions: �optimal� (O), using maximal open throat, �sub-optimal� (SO), using reduced open throat and loud sub-optimal (LSO) to control for the effect of loudness. From these recordings, acoustic characteristics of vibrato (Mitchell & Kenny, 2004b) and energy distribution (Mitchell & Kenny, 2004a) were examined. Subsequent investigations of the vibrato parameters of rate, extent and onset, revealed that extent was significantly reduced and onset increased when singers did not use the technique. As inconsistent vibrato is considered indicative of poor singing, it was hypothesized that testing the energy distribution in these singers� voices in each condition would identify the timbral changes associated with open throat. Visual inspection of long term average spectra (LTAS) confirmed differences between O and SO, but conventional measures applied to long term average spectra (LTAS), comparing energy peak height [singing power ratio (SPR)] and peak area [energy ratio (ER)] were not sensitive to the changes identified through visual inspection of the LTAS. These results were not consistent with the vibrato findings and suggest that conventional measures of SPR and ER are not sufficiently sensitive to evaluate LTAS. In the fourth study, fifteen expert listeners consistently and reliably identified the presence of open throat technique with 87% accuracy (Mitchell & Kenny, in press). In the fifth study, LTAS measurements were examined with respect to the perceptual ratings of singers. There was no relationship between perceptual rankings of vocal beauty and acoustic rankings of vocal quality (Kenny & Mitchell, 2004, in press). There is a vast literature of spectral energy definitions of good voice but the studies in this thesis have indicated that current acoustic methods are limited in defining vocal quality. They also suggest that current work in singing has not sufficiently incorporated perceptual ratings and descriptions of sound quality or the relationship between acoustic and perceptual factors with pedagogical practices.

Concepts of choral and solo singing diverge among the masses of pedagogues, teachers, and conductors who have differing opinions about healthy vocal technique and training. These differences have generated tension within some university music programs, with choral faculty and voice faculty sometimes on opposing sides. This document presents answers from professional singers who engage in choral and solo singing while maintaining a healthy vocal technique. All subjects interviewed for this document were asked to speak in detail to vocal adjustments made to sing in different styles. In addition, they were asked to identify any vocal faults that may arise from improper vocal production. The goal of this document is to lay grounds for valuable discussion regarding the opposing perspectives found in some academic circles with regard to proper vocal technique and training for choral and solo singing.

Modulation of voice is a result of physiologic oscillation within one or more components of the vocal system including the breathing apparatus (i.e., pressure supply), the larynx (i.e. sound source), and the vocal tract (i.e., sound filter). These oscillations may be caused by pathological tremor associated with neurological disorders like essential tremor or by volitional production of vibrato in singers. Because the acoustical characteristics of voice modulation specific to each component of the vocal system and the effect of these characteristics on perception are not well-understood, it is difficult to assess individuals with vocal tremor and to determine the most effective interventions for reducing the perceptual severity of the disorder. The purpose of the present studies was to determine how the acoustical characteristics associated with laryngeal-based vocal tremor affect the perception of the magnitude of voice modulation, and to determine if adjustments could be made to the voice source and vocal tract filter to alter the acoustic output and reduce the perception of modulation. This research was carried out using both a computational model of speech production and trained singers producing vibrato to simulate laryngeal-based vocal tremor with different voice source characteristics (i.e., vocal fold length and degree of vocal fold adduction) and different vocal tract filter characteristics (i.e., vowel shapes). It was expected that, by making adjustments to the voice source and vocal tract filter that reduce the amplitude of the higher harmonics, the perception of magnitude of voice modulation would be reduced. The results of this study revealed that listeners' perception of the magnitude of modulation of voice was affected by the degree of vocal fold adduction and the vocal tract shape with the computational model, but only by the vocal quality (corresponding to the degree of vocal fold adduction) with the female singer. Based on regression analyses, listeners' judgments were predicted by modulation information in both low and high frequency bands. The findings from these studies indicate that production of a breathy vocal quality might be a useful compensatory strategy for reducing the perceptual severity of modulation of voice for individuals with tremor affecting the larynx.

The technique of �open throat� is a pedagogical concept transmitted through the oral tradition of singing. This thesis explored the pedagogical perceptions and practices of �open throat� using empirical methodologies to assess technical skill and associated vocal quality. In the first study (Mitchell, Kenny, Ryan, & Davis, 2003), we assessed the degree of consensus amongst singing pedagogues regarding the definition of, and use in the singing studio of the technique called �open throat.� Results indicated that all fifteen pedagogues described �open throat� technique as fundamental to singing training and were positive about the sound quality it achieved, especially in classical singing. It was described as a way of maximising pharyngeal space or abducting the false vocal folds. Hypotheses generated from pedagogical beliefs expressed in this first study were then tested acoustically (Mitchell & Kenny, 2004a, 2004b). Six advanced singing students sang in two conditions: �optimal� (O), using maximal open throat, �sub-optimal� (SO), using reduced open throat and loud sub-optimal (LSO) to control for the effect of loudness. From these recordings, acoustic characteristics of vibrato (Mitchell & Kenny, 2004b) and energy distribution (Mitchell & Kenny, 2004a) were examined. Subsequent investigations of the vibrato parameters of rate, extent and onset, revealed that extent was significantly reduced and onset increased when singers did not use the technique. As inconsistent vibrato is considered indicative of poor singing, it was hypothesized that testing the energy distribution in these singers� voices in each condition would identify the timbral changes associated with open throat. Visual inspection of long term average spectra (LTAS) confirmed differences between O and SO, but conventional measures applied to long term average spectra (LTAS), comparing energy peak height [singing power ratio (SPR)] and peak area [energy ratio (ER)] were not sensitive to the changes identified through visual inspection of the LTAS. These results were not consistent with the vibrato findings and suggest that conventional measures of SPR and ER are not sufficiently sensitive to evaluate LTAS. In the fourth study, fifteen expert listeners consistently and reliably identified the presence of open throat technique with 87% accuracy (Mitchell & Kenny, in press). In the fifth study, LTAS measurements were examined with respect to the perceptual ratings of singers. There was no relationship between perceptual rankings of vocal beauty and acoustic rankings of vocal quality (Kenny & Mitchell, 2004, in press). There is a vast literature of spectral energy definitions of good voice but the studies in this thesis have indicated that current acoustic methods are limited in defining vocal quality. They also suggest that current work in singing has not sufficiently incorporated perceptual ratings and descriptions of sound quality or the relationship between acoustic and perceptual factors with pedagogical practices.

Thesis (Ed.D.)--University of Illinois at Urbana-Champaign, 1997. / Includes bibliographical references (leaves 95-103).

No description available.

An investigation was done on the methods used by performers of classical flute music to improve their flute tone. A literature study was done and a methodology created. This resulted in detailed dissection and then discussion of the various aspects that influence flute tone. Thereafter a series of practice charts were developed, which can be used to guide performers, students and teachers in their experiment to improve and diversify flute tone. The key areas of flute tone that were examined are: embouchure, lip flexibility, vibrato and tone colour. It has been found that different methods work for different people to improve their flute tone, and therefore personal experimentation is necessary in order to achieve the required tone, which also depends on personal taste. / Dissertation (MMus (Performing Art))--University of Pretoria, 2006. / Music / MMus / unrestricted

Research in vocal vibrato has established that vocal tract filtering is primarily responsible for the amplitude modulation (AM) present in Western classical vibrato. Using electroglottography (EGG) and the EGG speed quotient, which is sensitive to fluctuations in the amplitude of vocal fold vibration, AM was detected at the laryngeal (source) level, in addition to the subsequent AM which results from vocal tract filtering. Seventeen classically-trained opera singers sang vowels in three pitch and loudness conditions. EGG and microphone measurements of FM and AM and their rates, extents, and periodicity were made. Airflow was also measured, and the samples were rated by voice professors for vibrato consistency, speed, and width. Physiologic and acoustic data revealed that AM from vocal tract filtering, or the resonance-harmonics interaction (RHI) described by Horii and associates, was present throughout the vibrato samples. Laryngeal-level AM was also present throughout, with soft conditions having the highest mean extents. Singers with lower degrees of laryngeal-level AM were also those rated highest for vibrato consistency. Vibrato rate increased as pitch increased, and, to a lesser extent, as intensity increased. These findings document, in addition to the AM resulting from the RHI, the concurrent presence of laryngeal-level AM in a group of singers representing a range of training and experience.

Ce travail concerne la segmentation et l'indexation des signaux sonores musicaux. Trois niveaux de segmentation interdépendants sont définis, correspondant chacun à un niveau de description du son différent.<br /><br /><br />1) Le premier niveau de segmentation, appelé << sources >>, concerne la distinction entre la parole et la musique. Les sons considérés peuvent provenir par exemple de bandes-son de films ou d'émissions radiophoniques.<br /><br />Des fonctions d'observation sont étudiées, qui ont pour objectif de mettre en évidence les propriétés différentes du signal de parole et du signal de musique. Plusieurs méthodes de classification ont été étudiées. Les performances du système avec des signaux réels sont discutées.<br /><br /><br />2) Le deuxième niveau de segmentation, appelé << caractéristiques >>, concerne ce type d'index : silence/son, voisé/non voisé, harmonique/inharmonique, monophonique/polyphonique, avec vibrato/sans vibrato, avec trémolo/sans trémolo. La plupart de ces caractéristiques donnent lieu à des fonctions d'observation utilisées par le troisième niveau de segmentation.<br /><br />La détection du vibrato, l'estimation de ses paramètres (fréquence et amplitude) et sa suppression du trajet de la fondamentale ont été particulièrement étudiées. Un ensemble de techniques sont décrites. Les performances de ces techniques avec des sons réels sont discutées.<br /><br />Le vibrato est supprimé du trajet de la fondamentale original afin d'obtenir une ligne mélodique << lissée >>. Alors, ce nouveau trajet de la fondamentale peut être utilisé pour la segmentation en notes (troisième niveau de segmentation) des extraits musicaux, et peut aussi être utilisé pour des modifications de ces sons.<br /><br />La détection du vibrato est opérée seulement si, lors du premier niveau de segmentation, c'est la source << musique >> qui a été détectée.<br /><br /><br />3) Le troisième niveau de segmentation concerne la segmentation en << notes ou en phones ou plus généralement en parties stables >>, suivant la nature du son considéré : instrumental, voix chantée, parole, son percussif...<br /><br />L'analyse est composée de quatre étapes. La première consiste à extraire un grand nombre de fonctions d'observation. Une fonction d'observation est d'autant plus appropriée qu'elle présente des pics grands et fins quand des transitions surviennent et que sa moyenne et sa variance restent petites pendant les zones stables. Trois types de transitions existent : celles en fréquence fondamentale, celles en énergie et celles en contenu spectral. En deuxième lieu, chaque fonction d'observation est automatiquement seuillée. En troisième lieu, une fonction de décision finale, correspondant aux marques de segmentation, est construite à partir des fonctions d'observation seuillées. Finalement, pour les sons monophoniques et harmoniques, la transcription automatique est effectuée. Les performances du système avec des sons réels sont discutées.<br /><br /><br />Les données obtenues pour un certain niveau de segmentation sont utilisées par les niveaux de segmentation de numéro d'ordre supérieurs afin d'améliorer leurs performances. <br /><br />La longueur des segments donnés par le niveau de segmentation en << sources >> peut être de quelques minutes. La longueur des segments donnés par le niveau de segmentation en << caractéristiques >> est communément plus petite : elle est disons de l'ordre de quelques dizaines de secondes. La longueur des segments donnés par le niveau de segmentation en << zones stables >> est le plus souvent inférieure à une seconde.

Elements of continuous variation such as tremolo, vibrato and portamento enable dimensions of their own in expressive melodic music in styles such as in Indian Classical Music. There is published work on parametrically modeling some of these elements individually, and to apply the modeled parameters to automatically generated musical notes in the context of machine musicianship, using simple rule-based mappings. There have also been many systems developed for generative musical accompaniment using probabilistic models of discrete musical elements such as MIDI notes and durations, many of them inspired by computational research in linguistics. There however doesn't seem to have been a combined approach of parametrically modeling expressive elements in a probabilistic framework. This documents presents a real-time computational framework that uses a multi-attribute trie / n-gram structure to model parameters like frequency, depth and/or lag of the expressive variations such as vibrato and portamento, along with conventionally modeled elements such as musical notes, their durations and metric positions in melodic audio input. This work proposes storing the parameters of expressive elements as metadata in the individual nodes of the traditional trie structure, along with the distribution of their probabilities of occurrence. During automatic generation of music, the expressive parameters as learned in the above training phase are applied to the associated re-synthesized musical notes. The model is aimed at being used to provide automatic melodic accompaniment in a performance scenario. The parametric modeling of the continuous expressive elements in this form is hypothesized to be able to capture deeper temporal relationships among musical elements and thereby is expected to bring about a more expressive and more musical outcome in such a performance than what has been possible using other works of machine musicianship using only static mappings or randomized choice. A system was developed on Max/MSP software platform with this framework, which takes in a pitched audio input such as human singing voice, and produces a pitch track which may be applied to synthesized sound of a continuous timbre. The system was trained and tested with several vocal recordings of North Indian Classical Music, and a subjective evaluation of the resulting audio was made using an anonymous online survey. The results of the survey show the output tracks generated from the system to be as musical and expressive, if not more, than the case where the pitch track generated from the original audio was directly rendered as output, and also show the output with expressive elements to be perceivably more expressive than the version of the output without expressive parameters. The results further suggest that more experimentation may be required to conclude the efficacy of the framework employed in relation to using randomly selected parameter values for the expressive elements. This thesis presents the scope, context, implementation details and results of the work, suggesting future improvements.