Acoustics of the trained versus untrained singing voice:

Prevalence of Dysphonia in Metal Singers and the Impact of Vocal Education: A Subjective Analysis

On average, the prevalence of subjectively indicated dysphonia in singers is higher than in the general population. When using extreme vocal techniques supraglottic structures are involved to protect the vocal folds. Most of the metal singers learn this specific singing style autodidactically. Vocal training can have a positive effect on the voice and prevent voice problems. The aim of the study was to find out the prevalence of dysphonia in metal singers and the impact this has on the profession or the vocal education. The subjects had to fill out an online questionnaire including two validated and standardized questionnaires about the speaking and singing voice: The short version of the Voice Handicap Index (VHI 12) and the Singing Voice Handicap Index (SVHI). The prevalence of dysphonia in metal singers is 12.2%. 9 out of 74 participants showed an increased (S)VHI score. 6 of these participants learned singing autodidactically. No dysphonia was found in any singer who sings full-time or studied singing. The correlation between education or profession and dysphonia was statistically not significant. More women than men studied or took singing lessons. This difference was statistically significant. The prevalence of 12.2% in our study is quite low and contrary to our assumption. We can assume, that a vocal education for the metal singing style is useful but not mandatory and the number of persons with dysphonia through metal singing is low. A healthy vocal technique does not necessarily have to be the result of voice lessons.

Assessment of Tongue Position and Laryngeal Height in Two Professional Voice Populations

Purpose To advance our current knowledge of singer physiology by using ultrasonography in combination with acoustic measures to compare physiological differences between musical theater (MT) and opera (OP) singers under controlled phonation conditions. Primary objectives addressed in this study were (a) to determine if differences in hyolaryngeal and vocal fold contact dynamics occur between two professional voice populations (MT and OP) during singing tasks and (b) to determine if differences occur between MT and OP singers in oral configuration and associated acoustic resonance during singing tasks. Method Twenty-one singers (10 MT and 11 OP) were included. All participants were currently enrolled in a music program. Experimental procedures consisted of sustained phonation on the vowels /i/ and /ɑ/ during both a low-pitch task and a high-pitch task. Measures of hyolaryngeal elevation, tongue height, and tongue advancement were assessed using ultrasonography. Vocal fold contact dynamics were measured using electroglottography. Simultaneous acoustic recordings were obtained during all ultrasonography procedures for analysis of the first two formant frequencies. Results Significant oral configuration differences, reflected by measures of tongue height and tongue advancement, were seen between groups. Measures of acoustic resonance also showed significant differences between groups during specific tasks. Both singer groups significantly raised their hyoid position when singing high-pitched vowels, but hyoid elevation was not statistically different between groups. Likewise, vocal fold contact dynamics did not significantly differentiate the two singer groups. Conclusions These findings suggest that, under controlled phonation conditions, MT singers alter their oral configuration and achieve differing resultant formants as compared with OP singers. Because singers are at a high risk of developing a voice disorder, understanding how these two groups of singers adjust their vocal tract configuration during their specific singing genre may help to identify risky vocal behavior and provide a basis for prevention of voice disorders.

Individual Therapeutic Singing Program for Vocal Quality and Depression in Parkinson's Disease

OBJECTIVE

Patients with Parkinson's disease (PD) frequently experience depression associated with voice problems. Singing involves the use of similar muscles and the neural networks associated with vocal function and emotional response. The purpose of this study is to enhance vocal quality and depressive symptoms of patients with PD using individual singing program.

METHODS

The Individual Therapeutic Singing Program for PD (ITSP-PD) was conducted by a certified music therapist. In total, nine PD patients with a subjective voice problem or depression participated in 6 sessions over 2 weeks. We measured the Maximum Phonation Time (MPT) via the Praat test, the Voice Handicap Index (VHI), the Voice-Related Quality of Life (V-RQOL) and the Geriatric Depression Scale (GDS).

RESULTS

In total, 8 out of 9 patients completed all the sessions; 6 out of 8 patients participated in the follow-up test after 6 months. A statistically significant change in MPT (p = 0.011) was observed between the pre- and post-tests. The VHI (p = 0.035) and the GDS (p = 0.018) were significantly lower in the post-test. In the pre-, post-, and follow-up tests, the MPT (p = 0.030), V-RQOL (p = 0.008), and GDS (p = 0.009) were significantly changed.

CONCLUSION

The ITSP-PD based on neurological singing therapy for PD showed therapeutic possibility for vocal function and depression in patients with PD. Our findings suggest the need for a randomized study to examine the continuing positive effects of the ITSP-PD over a longer period of time.

Effects of Therapy With Semi-occluded Vocal Tract and Choir Training on Voice in Adult Individuals With Congenital, Isolated, Untreated Growth Hormone Deficiency

OBJECTIVES

Voice is produced by the vibration of the vocal folds expressed by its fundamental frequency (Hz), whereas the formants (F) are fundamental frequency multiples, indicating amplification zones of the vowels in the vocal tract. We have shown that lifetime isolated growth hormone deficiency (IGHD) causes high pitch voice, with higher values of most formant frequencies, maintaining a prepuberal acoustic prediction. The objectives of this work were to verify the effects of the therapy with a semi-occluded vocal tract (SOVTT) and choir training on voice in these subjects with IGHD. We speculated that acoustic vocal parameters can be improved by SOVTT or choir training.

STUDY DESIGN

This is a prospective longitudinal study without control group.

METHODS

Acoustic analysis of isolated vowels was performed in 17 adults with IGHD before and after SOVTT (pre-SOVTT and post-SOVTT) and after choir training (post training), in a 30-day period.

RESULTS

The first formant was higher in post training compared with the pre-SOVTT (P = 0.009). The second formant was higher in post-SOVTT than in pre-SOVTT (P = 0.045). There was a trend of reduction in shimmer in post-choir training in comparison with pre-SOVTT (P = 0.051), and a reduction in post-choir training in comparison with post-SOVTT (P = 0.047).

CONCLUSIONS

SOVTT was relevant to the second formant, whereas choir training improved first formant and shimmer. Therefore, this speech therapy approach was able to improve acoustic parameters of the voice of individuals with congenital, untreated IGHD. This seems particularly important in a scenario in which few patients are submitted to growth hormone replacement therapy.

Automatic Assessment of Acoustic Parameters of the Singing Voice: Application to Professional Western Operatic and Jazz Singers

INTRODUCTION

The obvious perceptual differences between various singing styles like Western operatic and jazz rely on specific dissimilarities in vocal technique. The present study focuses on differences in vibrato acoustics and in singer's formant as analyzed by a novel software tool, named BioVoice, based on robust high-resolution and adaptive techniques that have proven its validity on synthetic voice signals.

MATERIAL AND METHODS

A total of 48 professional singers were investigated (29 females; 19 males; 29 Western operatic; and 19 jazz). They were asked to sing "a cappella," but with artistic expression, a well-known musical phrase from Gershwin's Porgy and Bess, in their own style: either operatic or jazz. A specific sustained note was extracted for detailed vibrato analysis. Beside rate (s(-1)) and extent (cents), duration (seconds) and regularity were computed. Two new concepts are introduced: vibrato jitter and vibrato shimmer, by analogy with the traditional jitter and shimmer of voice signals. For the singer's formant, on the same sustained tone, the ratio of the acoustic energy in formants 1-2 to the energy in formants 3, 4, and 5 was automatically computed, providing a quality ratio (QR).

RESULTS

Vibrato rates did not differ among groups. Extent was significantly larger in operatic singers, particularly females. Vibrato jitter and vibrato shimmer were significantly smaller in operatic singers. Duration of vibrato was also significantly longer in operatic singers. QR was significantly lower in male operatic singers.

CONCLUSIONS

Some vibrato characteristics (extent, regularity, and duration) very clearly differentiate the Western operatic singing style from the jazz singing style. The singer's formant is typical of male operatic singers. The new software tool is well suited to provide useful feedback in a pedagogical context.

Características da espectrografia de banda larga e estreita da emissão vocal de homens com laringe sem afecções

OBJETIVO: caracterizar as espectrografias vocais de um grupo de homens adultos jovens. MÉTODO : 25 homens adultos jovens, sem queixas vocais, com diagnóstico otorrinolaringológico de laringe sem afecção, realizaram a emissão sustentada da vogal [a] em pé e com frequência e intensidade habituais. As emissões foram analisadas pelo programa Real Time Spectrogram da Kay Pentax®, que originou um espectrograma de banda larga e outro de banda estreita para cada sujeito. Estes foram duplicados, para aumentar a fidedignidade do estudo, e enviados a três fonoaudiólogas juízas que realizaram o julgamento dos mesmos seguindo um protocolo. Os resultados foram analisados estatisticamente pelo Teste para Diferenças de Proporções com nível de significância de 5 %. RESULTADOS: na Espectrografia de Banda Larga, houve significância estatística para ruído muito presente nas frequências em torno de 3,2KHz, pouca definição do terceiro formante, pouca regularidade do traçado e anti-ressonância mediana. Na Espectrografia de Banda Estreita, houve fraca intensidade das frequências em torno de 3,2KHz e em todo espectro, ruído muito presente em todo espectro e nas frequências em torno de 3,2KHz, ruído mediano nas baixas frequências, pouca regularidade do traçado e anti-ressonância mediana. CONCLUSÃO: a análise espectrográfica dos homens adultos jovens, com laringe sem afecções e sem queixas vocais, revelou grande quantidade de ruído em todo o espectro e nas frequências em torno de 3,2KHz, terceiro formante pouco definido, ruído mediano nas baixas frequências, traçado pouco regular, anti-ressonância mediana, fraca intensidade em todo espectro e, em especial, nas frequências em torno de 3,2KHz.