A Comparison of Countertenor Singing at Various Professional Levels Using Acoustic, Electroglottographic, and Videofluoroscopic Methods.

INTRODUCTION: The vocal characteristics of countertenors (CTTs) are poorly understood due to a lack of studies in this field. This study aims to explore differences among CTTs at various professional levels, examining both disparities and congruences in singing styles to better understand the CTT voice. MATERIALS AND METHODS: Four CTTs (one student, one amateur, and two professionals) sang "La giustizia ha già sull'arco" from Handel's Giulio Cesare, with concurrent videofluoroscopic, electroglottography (EGG), and acoustic data collection. Auditory-perceptual analysis was employed to rate professional level. Acoustic analysis included LH1-LH2, formant cluster prominence, and vibrato analysis. EGG data was analyzed using FonaDyn software, while anatomical modifications were quantified using videofluoroscopic images. RESULTS: CTTs exhibited EGG contact quotient values surpassing typical levels for inexperienced falsettos. Their vibrato characteristics aligned with expectations for classical singing, whereas the presence of the singer's formant was not observed. Variations in supraglottic adjustments among CTTs underscored the diversity of techniques employed by CTT singers. CONCLUSIONS: CTTs exhibited vocal techniques that highlighted the influence of individual preferences, professional experience, and stylistic choices in shaping their singing characteristics. The data revealed discernible differences between professional and amateur CTTs, providing insights into the impact of varying levels of experience on vocal expression.

A Comparison of the Effects of Phonation into a Positive Expiratory Pressure Device and Silicone Tube in Water on the Vocal Mechanism.

OBJECTIVES: Positive expiratory pressure (PEP) devices have become an additional therapeutic approach for treating voice disorders. Similar to water resistance therapy (WRT), phonation in a PEP device introduces a secondary source of vibration within the vocal tract. This investigation aimed to compare the effects of phonation using a PEP device and silicone tube phonation (STP) commonly used in WRT on the vocal mechanism during phonation. METHODS: Three normophonic subjects participated in the study. High-speed videoendoscopy, pressure, airflow, electroglottography, and acoustic recordings were collected. RESULTS: The results demonstrated that phonation using both the PEP device and silicone tube induced alterations in glottal behavior. The PEP device produced more pronounced and consistent pressure oscillations, impacting the glottal cycle and influencing parameters including contact quotient (CQ), fundamental frequency, glottal area, pressure, and airflow. The regular vibratory mechanism of the PEP device systematically modified the glottal cycle. In STP, regular bubbling at lower depths of submersion produced higher CQ values, supporting the efficacy of deep bubbling exercises for inducing glottal adduction. CONCLUSIONS: The findings suggest that phonation using PEP devices has a more pronounced impact on the vocal tract and glottis. It also provides a stronger massage effect that directly affects the glottal source. Phonation with a silicone tube produces similar results, although to a lesser extent and with lower regularity. These findings offer guidance in the selection of voice therapy devices.

Assessment of Changes in Laryngeal Configuration and Voice Parameters Among Different Frequencies of Neuromuscular Electrical Stimulation (NMES) and Cumulative Effects of NMES in a Normophonic Subject: A Pilot Study.

INTRODUCTION: Neuromuscular electrical stimulation (NMES) is a complementary resource to voice therapy that can be used for the treatment of hypofunctional voice disorders. Although positive clinical studies have been reported, neutral and even potentially harmful effects of NMES are also described in the literature. Furthermore, in the studies examined by the authors, the use of different methods of NMES have been identified, which further contributes to the inconsistent results found among studies. Moreover, limited rationale is provided for the chosen NMES parameters such as electrode placement, frequency of NMES and length of treatment. The aims of this pilot study were to investigate the a) impact of different frequencies of NMES on glottal configuration and vocal fold vibration patterns and b) changes in laryngeal configuration and vocal output across 12 minutes of NMES. METHOD: Three experiments were carried out looking at changes in laryngeal configuration and voice output using different imaging techniques (fibreoptic nasolaryngoscopy and high-speed video), acoustical analysis (F0, formant analysis, SPL, CPPS and LHSR values), electroglottography (EGG) and Relative Fundamental Frequency (RFF) analyses. Glottal parameters and acoustical measures were recorded before, during, and after stimulation. Data was collected at rest and during phonation. RESULTS: Overall the results showed global changes in laryngeal configuration from normal to hyperfunctional (ie, increased RFF, SPL, CQ, and stiffness). Changes were more pronounced for lower frequencies of NMES and were significant within less than three minutes of application. CONCLUSION: NMES is an effective resource for the activation of intrinsic laryngeal muscles producing significant levels of adduction within few minutes of application. Lower NMES frequencies produced greater muscle activation when compared to higher frequencies.

Pressure, Flow, and Glottal Area Waveform Profile Changes During Phonation Using the Acapella Choice Device.

INTRODUCTION: Vibratory positive expiratory pressure (PEP) devices are now commonly used as a resource for voice therapy. PEP devices promote improved vocal economy with the added benefit of producing a massage effect in the vocal tract. Although the benefits of PEP devices for voice have already been demonstrated, their impact on the vocal source is still not very clear. This study assesses the impact of phonation into the Acapella Choice (a type of PEP device) on the voice. METHODS: Three normophonic subjects underwent high-speed videoendoscopy assessment while pressure, flow and electroglottographic data was collected. RESULTS: Phonation into the Acapella device produces large changes in the pressure and flow profiles consequently affecting the voice source. In specific, when intraoral pressure increases as a consequence of the downward movement of the rocker arm in the Acapella device (reduction of the airflow outlet), phonation is hindered, demonstrated by the lower amplitude of vibration of the vocal folds and weaker modulation of the pressure and flow values by the glottal cycle. When the rocker arm in the Acapella device opens (increasing the airflow outlet), the opposite trend is observed where vocal fold vibration is aided and the modulation of pressure and flow by the vocal cycle increases. Based on the pressure and flow signals, we can assume that the impedance of the vocal tract alternates between two dominant regimes: increased inertive reactance (aided vibration) and increased resistance (hindered vibration). CONCLUSIONS: PEP devices, such as the Acapella device, are efficient in modulating the pressure and flow profiles in the vocal tract leading to the alternation of glottal vibration from aided to hindered. These changes in the glottal vibration can be considered an additional consequence of the massage effect caused by the Acapella device.

The subjective relevance of perceived sound aspects in remote singing education.

One of the consequences of the pandemic is a transition to remote education and the use of network audiovisual communication tools for education in musical disciplines. The circumstances of such education can differ and might influence the perceived sound or the education. The research observes the ratings of perceived aspects in singing lessons taught in three settings (common, reference, and direct). A variance of several aspects that relate to the perceived sound (temporal qualities and qualities of the sound and room) is observed in the remote forms, suggesting that these can be impaired in some settings and significant in the experience. The findings are discussed in relation to the perceived conditions and present practice.

Listening evaluation and classification of female singing voice categories.

Objective: Classification of voices into types depends on several factors: physiological - the size of the laryngeal and vocal tracts; acoustic-musically acceptable vocal range; position of formants; and properties of timbre. The aim of the study is to verify whether a group of experienced voice pedagogues and singers can determine the vocal type of the artist based on listening to a part of the aria better than a group of musicians can, and to determine what acoustic properties of the recordings are linked with the perceptual results of their evaluation.Methods: Freely available recordings of 11 females of different vocal categories of Rossini's aria "Una voce poco fa" from the opera Il Barbiere di Seviglia were selected for listening tests performed on examples of recitatives and coloraturas. Seven voice teachers (experienced group) and seven musicians non-teachers (laypeople group) evaluated the properties of the vocal category, timbre (dark-bright), resonance, vowel placement, suitability of vibrato, aesthetic impression, and voice flexibility.Results: The results showed a significantly higher inter-judge reliability in the experienced group. The highest reliability was achieved in timbre and vocal category evaluation, the least consistent was the evaluation of resonance. Factor analysis of the assessment variability showed dependent ratings of the vocal category, brightness and vowel placement for both groups in recitative. The experienced group similarly evaluated the brightness and the vocal category in coloratura. Assessment of the vocal category correlated with the reported categories of singers only in the experienced group. The categories mezzo-soprano and soprano were differentiated by spectral levels (based on FFT analysis of whole stimuli) in the 3.5-4.1 kHz spectral band in the recitative and in the 1.3-2.1 kHz and around 2.5 kHz bands in coloratura, and by the position of the local minimum after the fifth maximum for both kinds of stimuli.Conclusions: By means of correlation with ratings by experienced listeners, it is demonstrated that the voice category is mainly connected with the levels of specific spectral peaks, while brightness is correlated with the frequency positions of spectral maxima.

Medialization thyroplasty with a customized silicone implant: clinical experience.

The authors implemented medialization thyroplasty with a customized silicone implant in a total of 43 operations (36 patients) in 1999-2003. In 5 of these patients, the medialization thyroplasty was combined with cricothyroid subluxation (3 cases) or adduction of arytenoid cartilage (3 cases). One patient received medialization thyroplasty, cricothyroid subluxation and adduction of arytenoid cartilage. Postoperatively 36 patients reported substantial reduction of their complaints, 5 patients found their voice improved and only 2 patients (5.6%) stated that their voice had not changed. The subjective evaluation was consistent with the findings of laryngoscopy and the preoperative and postoperative phonation parameters (maximum phonation time, maximum sound pressure level, jitter and shimmer). Average maximum phonation time was 6.5 s before surgery and 12.5 s after surgery. Maximum vocal sound pressure level was, on average, about 4 dB higher after surgery. Jitter was reduced from 5.3 to 3.7% and shimmer from 32.3 to 18.6%. The differences between presurgical and postsurgical parameters in our study were all statistically significant, indicating voice improvement. Medialization thyroplasty with a silicone implant was proven to be a successful and safe surgical method for the treatment of vocal fold paralysis.