| 1. |
- Baptista La, Filipa Martins, et al.
(författare)
-
Pregnancy and the Singing Voice : Reports From a Case Study
- 2012
-
Ingår i: Journal of Voice. - : Elsevier BV. - 0892-1997 .- 1873-4588. ; 26:4, s. 431-439
-
Tidskriftsartikel (refereegranskat)abstract
- Objectives. Significant changes in body tissues occur during pregnancy; however, literature concerning the effects of pregnancy on the voice is sparse, especially concerning the professional classically trained voice. Hypotheses. Hormonal variations and associated bodily changes during pregnancy affect phonatory conditions, such as vocal fold motility and glottal adduction. Design. Longitudinal case study with a semiprofessional classically trained singer. Methods. Audio, electrolaryngograph, oral pressure, and air flow signals were recorded once a week during the last 12 weeks of pregnancy, 48 hours after birth and during the following consecutive 11 weeks. Vocal tasks included diminuendo sequences of the syllable /pae/sung at various pitches, and performing a Lied. Phonation threshold pressures (PTPs) and collision threshold pressures (CTPs), normalized amplitude quotient (NAQ), alpha ratio, and the dominance of the voice source fundamental were determined. Concentrations of sex female steroid hormones were measured on three occasions. A listening test of timbral brightness and vocal fatigue was carried out. Results. Results demonstrated significantly elevated concentrations of estrogen and progesterone during pregnancy, which were considerably reduced after birth. During pregnancy, CTPs and PTPs were high; and NAQ, alpha ratio, and dominance of the voice source fundamental suggested elevated glottal adduction. In addition, a perceptible decrease of vocal brightness was noted. Conclusions. The elevated CTPs and PTPs during pregnancy suggest reduced vocal fold motility and increased glottal adduction. These changes are compatible with expected effects of elevated concentrations of estrogen and progesterone on tissue viscosity and water retention.
|
|
| 2. |
- Borch, Daniel Zangger, et al.
(författare)
-
Some phonatory and resonatory characteristics of the rock, pop, soul, and Swedish dance band styles of singing
- 2011
-
Ingår i: Journal of Voice. - : Elsevier BV. - 0892-1997 .- 1873-4588. ; 25:5, s. 532-537
-
Tidskriftsartikel (refereegranskat)abstract
- This investigation aims at describing voice function of four nonclassical styles of singing, Rock, Pop, Soul, and Swedish Dance Band. A male singer, professionally experienced in performing in these genres, sang representative tunes, both with their original lyrics and on the syllable /pae/. In addition, he sang tones in a triad pattern ranging from the pitch Bb2 to the pitch C4 on the syllable /pae/ in pressed and neutral phonation. An expert panel was successful in classifying the samples, thus suggesting that the samples were representative of the various styles. Subglottal pressure was estimated from oral pressure during the occlusion for the consonant [p]. Flow glottograms were obtained from inverse filtering. The four lowest formant frequencies differed between the styles. The mean of the subglottal pressure and the mean of the normalized amplitude quotient (NAQ), that is, the ratio between the flow pulse amplitude and the product of period and maximum flow declination rate, were plotted against the mean of fundamental frequency. In these graphs, Rock and Swedish Dance Band assumed opposite extreme positions with respect to subglottal pressure and mean phonation frequency, whereas the mean NAQ values differed less between the styles.
|
|
| 3. |
- Dong, Li, et al.
(författare)
-
Loudness and Pitch of Kunqu Opera
- 2014
-
Ingår i: Journal of Voice. - : Elsevier BV. - 0892-1997 .- 1873-4588. ; 28:1, s. 14-19
-
Tidskriftsartikel (refereegranskat)abstract
- Equivalent sound level (Leq), sound pressure level (SPL), and fundamental frequency (F-0) are analyzed in each of five Kunqu Opera roles, Young girl and Young woman, Young man, Old man, and Colorful face. Their pitch ranges are similar to those of some western opera singers (alto, alto, tenor, baritone, and baritone, respectively). Differences among tasks, conditions (stage speech, singing, and reading lyrics), singers, and roles are examined. For all singers, Leq of stage speech and singing were considerably higher than that of conversational speech. Interrole differences of Leq among tasks and singers were larger than the intrarole differences. For most roles, time domain variation of SPL differed between roles both in singing and stage speech. In singing, as compared with stage speech, SPL distribution was more concentrated and variation of SPL with time was smaller. With regard to gender and age, male roles had higher mean Leq and lower average F-0, MF0, as compared with female roles. Female singers showed a wider F-0 distribution for singing than for stage speech, whereas the opposite was true for male singers. The Leq of stage speech was higher than in singing for young personages. Younger female personages showed higher Leq, whereas older male personages had higher Leq. The roles performed with higher Leq tended to be sung at a lower MF0.
|
|
| 4. |
- Echternach, Matthias, et al.
(författare)
-
High-Speed Imaging and Electroglottography Measurements of the Open Quotient in Untrained Male Voices' Register Transitions
- 2010
-
Ingår i: Journal of Voice. - : Elsevier BV. - 0892-1997 .- 1873-4588. ; 24:6, s. 644-650
-
Tidskriftsartikel (refereegranskat)abstract
- Vocal fold oscillation patterns in vocal register transitions are still unclarified. The vocal fold oscillations and the open quotient were analyzed with high-speed digital imaging (HSDI) and electroglottography (EGG) in 18 male untrained subjects singing a glissando from modal to the falsetto register. Results reveal that the open quotient changed with register in both HSDI. and EGG. The in-class correlations for different HSDI and EGG determinations of the open quotient were high. However, we found only weak interclass correlations between both methods. In ID subjects, irregularities of vocal fold vibration occurred during the register transition. Our results confirm previous observations that falsetto register is associated with a higher open quotient compared with modal register. These data suggest furthermore that irregularities typically observed in audio and electroglottographic signals during register transitions are caused by irregularities in vocal fold vibration.
|
|
| 5. |
- Echternach, Matthias, et al.
(författare)
-
Perturbation Measurements in Untrained Male Voices' Transitions From Modal to Falsetto Register
- 2011
-
Ingår i: Journal of Voice. - : Elsevier BV. - 0892-1997 .- 1873-4588. ; 25:6, s. 663-669
-
Tidskriftsartikel (refereegranskat)abstract
- Purpose. Voice periodicity during transitions from modal to falsetto register still remains an unclarified question. Method. We examined the acoustic and electroglottographic signals of 20 healthy untrained male voices' transitions from modal to falsetto register on the vowels /a, e, i, o, u, and ae/. Results. In addition to discontinuities in fundamental frequency (F0), an independent increase of jitter, relative average perturbation, and shimmer was observed during and apparently caused by the register transition. In falsetto, the jitter was higher than in the modal register. The contact quotient derived from the electroglottographic signal tended to be lower for higher than for lower F0. Conclusion. Register transitions are associated with increase of perturbation.
|
|
| 6. |
- Echternach, Matthias, et al.
(författare)
-
Vocal Tract in Female Registers : A Dynamic Real-Time MRI Study
- 2010
-
Ingår i: Journal of Voice. - : Elsevier BV. - 0892-1997 .- 1873-4588. ; 24:2, s. 133-139
-
Tidskriftsartikel (refereegranskat)abstract
- The area of vocal registers is still unclarified. In a previous investigation, dynamic real-time magnetic resonance imaging (MRI), which is able to produce up to 10 frames per second, was successfully applied for examinations of vocal tract modifications in register transitions in male singers. In the present study, the same MRI technique was used to study vocal tract shapes during four professional young sopranos' lower and upper register transitions. The subjects were asked to sing a scale on the vowel /a/ across their transitions. The transitions were acoustically identified by four raters. In neither of these transitions, clear vocal tract changes could be ascertained. However, substantial changes, that is, widening of the lips, opening of the jaw, elevation of the tongue dorsum, and continuous widening of the pharynx, were observed when the singers reached fundamental frequencies that were close to the frequency of the first formant of the vowel sung. These findings suggest that in these subjects register transition was not primarily the result of modifications of the vocal tract.
|
|
| 7. |
- Enflo, Laura, et al.
(författare)
-
Collision and Phonation Threshold Pressures Before and After Loud, Prolonged Vocalization in Trained and Untrained Voices
- 2013
-
Ingår i: Journal of Voice. - : Elsevier BV. - 0892-1997 .- 1873-4588. ; 27:5, s. 527-530
-
Tidskriftsartikel (refereegranskat)abstract
- The phonation threshold pressure (PTP) is defined as the lowest subglottal pressure needed for obtaining and sustaining vocal fold oscillation. It has been found to increase during vocal fatigue. In the present study, PTP is measured together with the threshold pressure needed for vocal fold collision; henceforth, the collision threshold pressure (CTP). PTP and CTP are compared before and after loud, prolonged vocalization in singer and nonsinger voices. Ten subjects repeated the vowel sequence /a, e, i, o, u/ at a Sound Pressure Level of at least 80 dB at 0.3 m for 20 minutes. Audio and electroglottography signals were recorded before and after this exercise. At the same time, oral pressure was registered while the subjects produced a diminuendo repeating the syllable /pa:/, thus acquiring an approximate of the subglottal pressure. CTP and PTP increased significantly after the vocal loading in the nonsinger subjects. On the other hand, singers reported no substantial effect of the exercise, and most singers had a mean after-to-before ratio close to 1 for both CTP and PTP.
|
|
| 8. |
|
|
| 9. |
|
|
| 10. |
- Karlsson, Fredrik, 1975-, et al.
(författare)
-
Letter to the Editor
- 2012
-
Ingår i: Journal of Voice. - : Elsevier. - 0892-1997 .- 1873-4588. ; 26:5
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
|
|
| 11. |
- Lamarche, Anick, 1977-, et al.
(författare)
-
The Singer’s Voice Range Profile : Female Professional Opera Soloists
- 2010
-
Ingår i: Journal of Voice. - : Elsevier BV. - 0892-1997 .- 1873-4588. ; 24:4, s. 410-426
-
Tidskriftsartikel (refereegranskat)abstract
- This work concerns the collection of 30 Voice Range Profiles (VRPs) of female operatic voice . Objectives: We address the questions: Is there a need for a singer’s protocol in VRP aquisition? Are physiological measurements sufficient or should the measurement of performance capabilities also be included? Can we address the female singing voice in general or is there a case for categorizing voices when studying phonetographic data? Method: Subjects performed a series of structured tasks involving both standard speech voice protocols and additional singing tasks. Singers also completed an extensive questionnaire. Results: Physiological VRPs differ from performance VRPs. Two new VRP metrics: the voice area above a defined level threshold, and the dynamic range independent from F0, were found to be useful in the analysis of singer VRP’s. Task design had no effect on performance VRP outcomes. Voice category differences were mainly attributable to phonation frequency based information. Conclusion: Results support the clinical importance of addressing the vocal instrument as it is used in performance. Equally important is the elaboration of a protocol suitable for the singing voice. The given context and instructions can be more important than task design for performance VRPs. Yet, for physiological VRP recordings, task design remains critical. Both types of VRPs are suggested for a singer’s voice evaluation.
|
|
| 12. |
- Lindström, Fredric, 1974, et al.
(författare)
-
Mean F0 values obtained through standard phrase pronunciation compared with values obtained from the normal work environment: A study on teacher and child voices performed in a pre-school environment
- 2010
-
Ingår i: Journal of Voice. - 0892-1997. ; 24:3, s. 319-323
-
Tidskriftsartikel (refereegranskat)abstract
- Mean fundamental frequency (F0) values are often used in research on vocal load. In this study, we examine how the mean F0 differs when evaluated through pronouncing a standard phrase as compared to the mean F0 obtained in a real work/play environment. We also examine how the F0 values change throughout the day. The study was performed in a preschool, nine adult female preschool teachers and 11 children participated. The participants wore a digital recorder equipped with an accelerometer, which was attached to the neck. In the study, the participant first pronounced a standard phrase in a controlled environment; thereafter, the voice was recorded in the environment where both children and adults normally reside throughout the day, denoted by the work/play environment. For each participant, the procedure was repeated four times throughout the day. Analyses showed that the F0 values of the children's and adult's voices were significantly higher when recorded in the work/play environment as compared to the controlled environment. The average difference was 36 Hz for adults and 24 Hz for children. Previous studies have shown an increase of F0 over the day for teachers. In this study, an increase between morning and afternoon values was found amounting to 8 Hz for adults and 24 Hz for children. For the child population, this increase was statistically significant. However, the total changes over the day revealed a somewhat more complex scheme, with an increase of F0 in the morning, a decrease during lunch, and finally an increase in the afternoon. This pattern was verified statistically for the joint child-adult population.
|
|
| 13. |
- Lindström, Fredric, 1974, et al.
(författare)
-
Observations of the Relationship Between Noise Exposure and Preschool Teacher Voice Usage in Day-Care Center Environments
- 2011
-
Ingår i: Journal of Voice. - : Elsevier BV. - 0892-1997 .- 1873-4588. ; 25:2, s. 166-172
-
Tidskriftsartikel (refereegranskat)abstract
- Although the relationship between noise exposure and vocal behavior (the Lombard effect) is well established, actual vocal behavior in the workplace is still relatively unexamined. The first purpose of this study was to investigate correlations between noise level and both voice level and voice average fundamental frequency (F-0) for a population of preschool teachers in their normal workplace. The second purpose was to study the vocal behavior of each teacher to investigate whether individual vocal behaviors or certain patterns could be identified. Voice and noise data were obtained for female preschool teachers (n = 13) in their workplace, using wearable measurement equipment. Correlations between noise level and voice level, and between voice level and F-0, were calculated for each participant and ranged from 0.07 to 0.87 for voice level and from 0.11 to 0.78 for F-0. The large spread of the correlation coefficients indicates that the teachers react individually to the noise exposure. For example, some teachers increase their voice-to-noise level ratio when the noise is reduced, whereas others do not.
|
|
| 14. |
- Lundeborg Hammarström, Inger, 1956-, et al.
(författare)
-
Acoustic and perceptual aspects of vocal function in children with adenotonsillar hypertrophy : effects of surgery
- 2012
-
Ingår i: Journal of Voice. - New York, USA : Mosby-Elsevier. - 0892-1997 .- 1873-4588. - 9789173933339 ; 26:4, s. 480-487
-
Tidskriftsartikel (refereegranskat)abstract
- Objective: To evaluate outcome of two types of tonsil surgery (tonsillectomy [TE] + adenoidectomy or tonsillotomy [TT] + adenoidectomy) on vocal function perceptually and acoustically.Study Design: Sixty-seven children, aged 50–65 months, on waiting list for tonsil surgery were randomized to TE (n = 33) or TT (n = 34). Fifty-seven age- and gender-matched healthy preschool children were controls. Twenty-eight of them, aged 48–59 months, served as control group before surgery, and 29, aged 60–71 months, served as control group after surgery.Methods: Before surgery and 6 months postoperatively, the children were recorded producing three sustained vowels (/ɑ/, /u/, and /i/) and 14 words. The control groups were recorded only once. Three trained speech and language pathologists performed the perceptual analysis using visual analog scale for eight voice quality parameters. Acoustic analysis from sustained vowels included average fundamental frequency, jitter percent, shimmer percent, noise-to-harmonic ratio, and the center frequencies of formants 1–3.Results: Before surgery, the children were rated to have more hyponasality and compressed/throaty voice (P < 0.05) and lower mean pitch (P < 0.01) in comparison to the control group. They also had higher perturbation measures and lower frequencies of the second and third formants. After surgery, there were no differences perceptually. Perturbation measures decreased but were still higher compared with those of control group (P < 0.05). Differences in formant frequencies for /i/ and /u/ remained. No differences were found between the two surgical methods.Conclusion: Voice quality is affected perceptually and acoustically by adenotonsillar hypertrophy. After surgery, the voice is perceptually normalized but acoustic differences remain. Outcome was equal for both surgical methods.
|
|
| 15. |
- Lyberg Åhlander, Viveka, et al.
(författare)
-
How Do Teachers With Self-Reported Voice Problems Differ From Their Peers With Self-Reported Voice Health?
- 2012
-
Ingår i: Journal of Voice. - : Elsevier BV. - 0892-1997. ; 26:4, s. 149-161
-
Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVES: This randomized case-control study compares teachers with self-reported voice problems to age-, gender-, and school-matched colleagues with self-reported voice health. The self-assessed voice function is related to factors known to influence the voice: laryngeal findings, voice quality, personality, psychosocial and coping aspects, searching for causative factors of voice problems in teachers. METHODS: Subjects and controls, recruited from a teacher group in an earlier questionnaire study, underwent examinations of the larynx by high-speed imaging and kymograms; voice recordings; voice range profile; audiometry; self-assessment of voice handicap and voice function; teaching and environmental aspects; personality; coping; burnout, and work-related issues. The laryngeal and voice recordings were assessed by experienced phoniatricians and speech pathologists. RESULTS: The subjects with self-assessed voice problems differed from their peers with self-assessed voice health by significantly longer recovery time from voice problems and scored higher on all subscales of the Voice Handicap Index-Throat. CONCLUSIONS: The results show that the cause of voice dysfunction in this group of teachers with self-reported voice problems is not found in the vocal apparatus or within the individual. The individual's perception of a voice problem seems to be based on a combination of the number of symptoms and of how often the symptoms occur, along with the recovery time. The results also underline the importance of using self-assessed reports of voice dysfunction.
|
|
| 16. |
- Lyberg Åhlander, Viveka, et al.
(författare)
-
Speaker's Comfort in Teaching Environments: Voice Problems in Swedish Teaching Staff.
- 2011
-
Ingår i: Journal of Voice. - : Elsevier BV. - 0892-1997. ; 25, s. 430-440
-
Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVES: The primary objective of this study was to examine how a group of Swedish teachers rate aspects of their working environment that can be presumed to have an impact on vocal behavior and voice problems. The secondary objective was to explore the prevalence of voice problems in Swedish teachers. METHOD: Questionnaires were distributed to the teachers of 23 randomized schools. Teaching staff at all levels were included, except preschool teachers and teachers at specialized, vocational high schools. The response rate was 73%. RESULTS: The results showed that 13% of the whole group reported voice problems occurring sometimes, often, or always. The teachers reporting voice problems were compared with those without problems. There were significant differences among the groups for several items. The teachers with voice problems rated items on room acoustics and work environment as more noticeable. This group also reported voice symptoms, such as hoarseness, throat clearing, and voice change, to a significantly higher degree, even though teachers in both groups reported some voice symptoms. Absence from work because of voice problems was also significantly more common in the group with voice problems-35% versus 9% in the group without problems. CONCLUSION: We may conclude that teachers suffering from voice problems react stronger to loading factors in the teaching environment, report more frequent symptoms of voice discomfort, and are more often absent from work because of voice problems than their voice-healthy colleagues.
|
|
| 17. |
- Lyberg Åhlander, Viveka, et al.
(författare)
-
Teachers' Voice Use in Teaching Environments: A Field Study Using Ambulatory Phonation Monitor.
- 2014
-
Ingår i: Journal of Voice. - : Elsevier BV. - 1873-4588 .- 0892-1997. ; 28:6, s. 5-841
-
Tidskriftsartikel (refereegranskat)abstract
- This case-control designed field study examines the vocal behavior in teachers with self-estimated voice problems (VP) and their age- and school-matched voice healthy (VH) colleagues. It was hypothesized that teachers with and teachers without VP use their voices differently regarding fundamental frequency, sound pressure level (SPL), and in relation to the background noise.
|
|
| 18. |
- McAllister, Anita, et al.
(författare)
-
A Comparison of Recordings of Sentences and Spontaneous Speech : Perceptual and Acoustic Measures in Preschool Children's Voices.
- 2012
-
Ingår i: Journal of Voice. - : Elsevier. - 0892-1997 .- 1873-4588. ; 26:5, s. 13-
-
Tidskriftsartikel (refereegranskat)abstract
- A well-controlled recording in a studio is fundamental in most voice rehabilitation. However, this laboratory like recording method has been questioned because voice use in a natural environment may be quite different. In children's natural environment, high background noise levels are common and are an important factor contributing to voice problems. The primary noise source in day-care centers is the children themselves. The aim of the present study was to compare perceptual evaluations of voice quality and acoustic measures from a controlled recording with recordings of spontaneous speech in children's natural environment in a day-care setting. Eleven 5-year-old children were recorded three times during a day at the day care. The controlled speech material consisted of repeated sentences. Matching sentences were selected from the spontaneous speech. All sentences were repeated three times. Recordings were randomized and analyzed acoustically and perceptually. Statistic analyses showed that fundamental frequency was significantly higher in spontaneous speech (P<0.01) as was hyperfunction (P<0.001). The only characteristic the controlled sentences shared with spontaneous speech was degree of hoarseness (Spearman's rho=0.564). When data for boys and girls were analyzed separately, a correlation was found for the parameter breathiness (rho=0.551) for boys, and for girls the correlation for hoarseness remained (rho=0.752). Regarding acoustic data, none of the measures correlated across recording conditions for the whole group.
|
|
| 19. |
- McDonnell, Maria, et al.
(författare)
-
Vocal Fold Vibration and Phonation Start in Aspirated, Unaspirated, and Staccato Onset
- 2011
-
Ingår i: Journal of Voice. - : Elsevier BV. - 0892-1997 .- 1873-4588. ; 25:5, s. 526-531
-
Tidskriftsartikel (refereegranskat)abstract
- Objectives/Hypotheses. Singers learn to produce well-controlled tone onsets by accurate synchronization of glottal adduction and buildup of subglottal pressure. Spectrographic analyses have shown that the higher spectrum partials are present also at the vowel onset in classically trained singers' performances. Such partials are produced by a sharp discontinuity in the waveform of the transglottal airflow, presumably produced by vocal fold collision. Study Design. After hearing a prompt series of a triad pattern, six singer subjects sang the same triad pattern on the vowel /i/ (1) preceded by an aspirated /p/, (2) preceded by an unaspirated /p/, and (3) without any preceding consonant in staccato. Methods. Using high-speed imaging we examined the initiation of vocal fold vibration in aspirated and unaspirated productions of the consonant /p/ as well as in the staccato tones. Results. The number vibrations failing to produce vocal fold collision were significantly higher in the aspirated /p/ than in the unaspirated /p/ and in the staccato tones. High frequency ripple in the audio waveform was significantly delayed in the aspirated /p/. Conclusions. Initiation of vocal fold collision and the appearance of high-frequency ripple in the vowel /i/ are slightly delayed in aspirated productions of a preceding consonant /p/.
|
|
| 20. |
- Morris, R.J., et al.
(författare)
-
Long-Term Average Spectra From a Youth Choir Singing in Three Vocal Registers and Two Dynamic Levels
- 2012
-
Ingår i: Journal of Voice. - : Elsevier BV. - 0892-1997 .- 1873-4588. ; 26:1, s. 30-36
-
Tidskriftsartikel (refereegranskat)abstract
- Objectives/HypothesisFew studies have reported the acoustic characteristics of youth choirs. In addition, scant data are available on youth choruses making the adjustments needed to sing at different dynamic levels in different registers. Therefore, the purpose of this study was to acoustically analyze the singing of a youth chorus to observe the evidence of the adjustments that they made to sing at two dynamic levels in three singing registers.Study DesignSingle-group observational study.MethodsThe participants were 47 members of the Brooklyn Youth Chorus who sang the same song sample in head, mixed, and chest voice at piano and forte dynamic levels. The song samples were recorded and analyzed using long-term average spectra and related spectral measures.ResultsThe spectra revealed different patterns among the registers. These differences imply that the singers were making glottal adjustments to sing the different register and dynamic level versions of the song. The duration of the closed phase, as estimated from the amplitudes of the first two harmonics, differed between the chest and head register singing at both dynamic levels. In addition, the spectral slopes differed among all three registers at both dynamic levels.ConclusionsThese choristers were able to change registers and dynamic levels quickly and with minimal prompting. Also, these acoustic measures may be a useful tool for evaluating some singing skills of young choristers.
|
|
| 21. |
- Nygren, M., et al.
(författare)
-
Gender Differences in Children's Voice Use in a Day Care Environment
- 2012
-
Ingår i: Journal of Voice. - : Elsevier BV. - 0892-1997 .- 1873-4588. ; 26:6
-
Tidskriftsartikel (refereegranskat)abstract
- Background. The prevalence of dysphonia is higher in boys than in girls before puberty. This could be because of the differences in boys' and girls' voice use. Previous research on gender differences in prepubescent children's voice parameters has been contradictory. Most studies have focused on examining fundamental frequency. Objectives. The purpose of this study was to investigate voice use in boys and girls in a day care environment based on the voice parameters fundamental frequency (Hz), vocal intensity (dB SPL), and phonation time (%) and to ascertain whether there were any significant gender differences. Study Design. Prospective comparative design. Method. The study was conducted in a day care environment where 30 children (17 boys and 13 girls aged 4-5 years) participated. The participants' voices were measured continuously for 4 hours with a voice accumulator that registered fundamental frequency, vocal intensity level, phonation time, and background noise. Results. Mean (standard deviation) fundamental frequency was 310 (22) and 321 (16) Hz, vocal intensity was 93 (4) and 91 (3) dB SPL, and phonation time was 7.7 (2.0)% and 7.6 (2.5)% for boys and girls, respectively. No differences between genders were statistically significant. Conclusion. The finding of no statistically significant gender differences for measurements of voice parameters in a group of children aged 4-5 years in a day care environment is an important finding that contributes to increased knowledge about young boys' and girls' voice use.
|
|
| 22. |
- Ohlsson, Ann-Christine, et al.
(författare)
-
Prevalence of Voice Symptoms and Risk Factors in Teacher Students
- 2012
-
Ingår i: Journal of Voice. - : Elsevier BV. - 0892-1997. ; 26:5, s. 629-634
-
Tidskriftsartikel (refereegranskat)abstract
- Teacher students seem to have low awareness of the vocal demands in their future professions, and students with vocal symptoms are at risk for developing voice disorders during their professional careers. The purpose of the present study was to determine the prevalence of voice problems in teacher students at the very beginning of their education at the university. Of 1636 students approached in the first couple of days, 1250 (76%) answered two questionnaires about voice symptoms, Screen6 and Swedish Voice Handicap Index (Sw-VHI), and one questionnaire about potential risk factors. A majority of the students were women, and their mean age was 23 years (range, 18-52 years). The results showed that 208 of 1250 students (17%) had voice problems, defined as at least two symptoms weekly or more often in Screen6. The proportion of women was larger in the group with voice problems than in the group without voice problems. Significant risk factors for voice problems were vocal fold problems in childhood and adulthood, frequent throat infections, airborne allergy, smoking, hearing problems, previous work as teacher or leader, voice demanding hobbies, and previous speech therapy or voice training. There was a clear association between the number of potential vocal risk factors and the number of voice symptoms. There was also a strong association between the scores of the two questionnaires, the Sw-VHI and the Screen6. Students with voice problems according to Screen6 scored 23.1 (mean Sw-VHI) compared with 7.8 for students without voice problems.
|
|
| 23. |
- Pabon, Peter, et al.
(författare)
-
Effects on Vocal Range and Voice Quality of Singing Voice Training : The Classically Trained Female Voice
- 2014
-
Ingår i: Journal of Voice. - : Elsevier. - 0892-1997 .- 1873-4588. ; 28:1, s. 36-51
-
Tidskriftsartikel (refereegranskat)abstract
- ObjectivesA longitudinal study was performed on the acoustical effects of singing voice training under a given study programme, using the Voice Range Profile (VRP). Study DesignPre- and post-training recordings were made of students that participated in a 3-year bachelor singing study programme. A questionnaire that included questions on optimal range, register use, classification, vocal health and hygiene, mixing technique, and training goals, was used to rate and categorize self-assessed voice changes. Based on the responses, a sub-group of 10 classically trained female voices was selected, that was homogeneous enough for effects of training to be identified. MethodsThe VRP perimeter contour was analyzed for effects of voice training. Also, a mapping within the VRP of voice quality, as expressed by the crest factor, was used to indicate the register boundaries and to monitor the acoustical consequences of the newly learned vocal technique of ‘mixed voice.’ VRP’s were averaged across subjects. Findings were compared to the self-assessed vocal changes. ResultsPre-post comparison of the average VRPs showed, in the midrange, (1) a decrease in the VRP area that was associated with the loud chest voice, (2) a reduction of the crest factor values, and (3) a reduction of maximum SPL values. The students’ self-evaluations of the voice changes appeared in some cases to contradict the VRP findings. ConclusionsVRP’s of individual voices were seen to change over the course of a singing education. These changes were manifest also in the group average. High resolution computerized recording, complemented with an acoustic register marker, allows a meaningful assessment of some effects of training, on an individual basis as well as for groups comprised of singers of a specific genre. It is argued that this kind of investigation is possible only within a focussed training programme, given by a faculty that has agreed on the goals.
|
|
| 24. |
- Schalling, E., et al.
(författare)
-
Effects of tactile biofeedback by a portable voice accumulator on voice intensity in speakers with Parkinson’s disease
- 2013
-
Ingår i: Journal of Voice. - : Elsevier BV. - 0892-1997 .- 1873-4588. ; 27:6, s. 729-737
-
Tidskriftsartikel (refereegranskat)abstract
- Objectives: To study the effects of biofeedback on voice sound level (SL) in subjects with reduced voice SL, secondary to Parkinson disease (PD), using a portable voice accumulator. Study Design: Prospective intervention study. Methods: Voice SL, phonation time, and level of background noise were registered with a portable voice accumulator during three consecutive registration periods. Six subjects with reduced voice SL secondary to PD participated. Biofeedback, in the form of a vibration signal when voice SL went below an individually set threshold level, was administered during the second registration period only. Mean voice SL was calculated for registration periods with and without feedback. Data on phonation time and level of background noise was also collected. Field registrations with the portable voice accumulator were also compared with registrations made in a recording studio. In addition, subjects were asked about subjective experiences of using the portable voice accumulator for up to 15 days. Results: There was a statistically significant increase in voice SL during the period when biofeedback of voice SL was administered. Subjects reported that using the portable voice accumulator was a positive experience. Several participants wished to continue using the device. In general, subjects handled the device independently with no major problems and did not report any negative experiences. Conclusions: Although this study was a first trial including six subjects with reduced voice SL secondary to PD, the findings indicate that biofeedback of voice SL administered via a portable voice accumulator may be a useful treatment tool for this group of patients and that further studies are needed.
|
|
| 25. |
|
|
| 26. |
- Sundberg, Johan, et al.
(författare)
-
Acoustical Study of Classical Peking Opera Singing
- 2012
-
Ingår i: Journal of Voice. - : Elsevier BV. - 0892-1997 .- 1873-4588. ; 26:2, s. 137-143
-
Tidskriftsartikel (refereegranskat)abstract
- Acoustic characteristics of classical opera singing differ considerably between the Western and the Chinese cultures. Singers in the classical Peking opera tradition specialize on one out of a limited number of standard roles. Audio and electroglottograph signals were recorded for four performers of the Old Man role and three performers of the Colorful Face role. Recordings were made of the singers' speech and when they sang recitatives and songs from their roles. Sound pressure level, fundamental frequency, and spectrum characteristics were analyzed. Histograms showing the distribution of fundamental frequency showed marked peaks for the songs, suggesting a scale tone structure. Some of the intervals between these peaks were similar to those used in Western music. Vibrato rate was about 3.5 Hz, that is, considerably slower than in Western classical singing. Spectra of vibrato-free tones contained unbroken series of harmonic partials sometimes reaching up to 17 000 Hz. Long-term-average spectrum (LTAS) curves showed no trace of a singer's formant cluster. However, the Colorful Face role singers' LTAS showed a marked peak near 3300 Hz, somewhat similar to that found in Western pop music singers. The mean LTAS spectrum slope between 700 and 6000 Hz decreased by about 0.2 dB/octave per dB of equivalent sound level.
|
|
| 27. |
- Sundberg, Johan, et al.
(författare)
-
Formant Tuning Strategies in Professional Male Opera Singers
- 2013
-
Ingår i: Journal of Voice. - : Elsevier BV. - 0892-1997 .- 1873-4588. ; 27:3, s. 278-288
-
Tidskriftsartikel (refereegranskat)abstract
- The term "formant tuning" is generally used for the case that one of the lowest formant frequencies coincides with the frequency of a source spectrum partial. Some authors claim that such coincidence is favorable and belongs to the goals of classical opera voice training, whereas other authors have found evidence for advising against it. This investigation analyzes the relationships between formant frequencies and partials in professional singers, who sang scales on the vowels /a/, /u/, /i/, and /ae/ in a pitch range including the passaggio, that is, the fundamental frequency range of approximately 300-400 Hz, applying either of the two singing strategies that are typically used (1) in classical and (2) in nonclassical singing, respectively. Formant frequencies of each note in the scales were measured by inverse-filtering the acoustic signal. In the classical style, the first formant tended to be lower than in the nonclassical style. Neither the first nor the second formant tended to change systematically between scale tones, such that on some scale tones either or both formants was just below, just above, or right on a spectrum partial. In many cases, singers produced similar spectrum characteristics of the top tones of the scales with different first and second formant frequencies. Regardless of whether the first formant was slightly lower, slightly higher, or right on a partial, the properties of the voice source did not seem to be affected.
|
|
| 28. |
- Sundberg, Johan, et al.
(författare)
-
Intonation and Expressivity : A Single Case Study of Classical Western Singing
- 2013
-
Ingår i: Journal of Voice. - : Elsevier BV. - 0892-1997 .- 1873-4588. ; 27:3, s. 391-
-
Tidskriftsartikel (refereegranskat)abstract
- Previous studies have shown that singers tend to sharpen phrase-peak tones as compared with equally tempered tuning ( ETT). Here we test the hypothesis that this can serve the purpose of musical expressivity. Data were drawn from earlier recordings, where a professional baritone sang excerpts as void of musical expression as he could (Neutral) and as expressive as in a concert (Concert). Fundamental frequency averaged over tones was examined and compared with ETT. Phrase-peak tones were sharper in excited examples, particularly in the Concert versions. These tones were flattened to ETT using the Melodyne software. The manipulated and original versions were presented pairwise to a musician panel that was asked to choose the more expressive version. By and large, the original versions were perceived as more expressive, thus supporting the common claim that intonation is a means for adding expressivity to a performance.
|
|
| 29. |
- Sundberg, Johan, et al.
(författare)
-
Subglottal Pressure Oscillations Accompanying Phonation
- 2013
-
Ingår i: Journal of Voice. - : Elsevier BV. - 0892-1997 .- 1873-4588. ; 27:4, s. 411-421
-
Tidskriftsartikel (refereegranskat)abstract
- Acoustic and aerodynamic properties of the voice source and vocal tract have been extensively analyzed during the last half century. Corresponding investigations of the subglottal system are rare but can be assumed to be relevant to voice production. In the present exploratory study, subglottal pressure was recorded in a male adult subject by means of tracheal puncture. Also recorded were the oral airflow and audio signals. Effects of vowel, phonation type, and vocal register shifts on the subglottal pressure waveform were examined. The moment of maximum flow declination rate was synchronous with the main positive peak of the subglottal pressure waveform. The three lowest subglottal resonance frequencies, determined by inverse filtering and long-term average spectra of the subglottal pressure during speech, were found to be about 500, 1220, and 2000 Hz, irrespective of supraglottal variations and phonation type. However, the subglottal pressure waveform was affected by the supraglottal formants, whereas the radiated vowel spectra did not show clear influence by the subglottal resonances. The fundamental frequency immediately preceding and immediately following a register break in pitch glides did not show systematic relationships with formants or with the lowest subglottal resonance.
|
|
| 30. |
- Sundberg, Johan, et al.
(författare)
-
Substyles of Belting : Phonatory and Resonatory Characteristics
- 2012
-
Ingår i: Journal of Voice. - : Elsevier BV. - 0892-1997 .- 1873-4588. ; 26:1, s. 44-50
-
Tidskriftsartikel (refereegranskat)abstract
- Belting has been described as speechlike, yell-like, or shouting voice production commonly used in contemporary commercial music genres and substantially differing from the esthetic of the Western classical voice tradition. This investigation attempts to describe phonation and resonance characteristics of different substyles of belting (heavy, brassy, ringy, nasal, and speechlike) and the classical style. A professional singer and voice teacher, skilled in these genres, served as the single subject. The recorded material was found representative according to a classification test performed by an expert panel. Subglottal pressure was measured as the oral pressure during the occlusion for the consonant vertical bar p vertical bar. The voice source and formant frequencies were analyzed by inverse filtering the audio signal. The subglottal pressure and measured flow glottogram parameters differed clearly between the styles heavy and classical assuming opposite extremes in most parameters. The formant frequencies, by contrast, showed fewer less systematic differences between the substyles but were clearly separated from the classical style with regard to the first formant. Thus, the differences between the belting substyles mainly concerned the voice source.
|
|
| 31. |
- Sundberg, Johan, et al.
(författare)
-
What is "Twang"?
- 2010
-
Ingår i: Journal of Voice. - : Elsevier BV. - 0892-1997 .- 1873-4588. ; 24:6, s. 654-660
-
Tidskriftsartikel (refereegranskat)abstract
- A single female professional vocal artist and pedagogue sang examples of "twang" and neutral voice quality, which a panel of experts classified, in almost complete agreement with the singer's intentions. Subglottal pressure was measured as the oral pressure during the occlusion during the syllable /pae/. This pressure tended to be higher in "twang," whereas the sound pressure level (SPL) was invariably higher. Voice source properties and formant frequencies were analyzed by inverse filtering. In "twang," as compared with neutral, the closed quotient was greater, the pulse amplitude and the fundamental were weaker, and the normalized amplitude tended to be lower, whereas formants 1 and 2 were higher and 3 and 5 were lower. The formant differences, which appeared to be the main cause of the SPL differences, were more important than the source differences for the perception of "twanginess." As resonatory effects occur independently of the voice source, the formant frequencies in "twang" may reflect a vocal strategy that is advantageous from the point of view of vocal hygiene.
|
|
| 32. |
- Sundberg, Johan, et al.
(författare)
-
Whispering : A Single-Subject Study of Glottal Configuration and Aerodynamics
- 2010
-
Ingår i: Journal of Voice. - : Elsevier BV. - 0892-1997 .- 1873-4588. ; 24:5, s. 574-584
-
Tidskriftsartikel (refereegranskat)abstract
- Whisper productions were produced by a single adult male subject over a wide range of subglottal pressures, glottal areas, and glottal flows. Dimensional measurements were made of these three variables, including glottal perimeter. Subglottal pressure was directly obtained by a pressure transducer in a tracheal catheter, and wide-band flow with a pneumotach mask. Four types of whispers were used-hyperfunctional, hypofunctional, neutral, and postphonation-in addition to three levels of loudness (soft, medium, loud). Sequences of the /pae/ syllable were used. Video recordings of the larynx were made. The glottis was outlined by hand with extrapolation for unseen parts, and area and perimeter were obtained through image analysis software. The whisper tokens resulted in the following wide ranges: subglottal pressure: 1.3-17 cm H2O; glottal flow: 0.9-1.71 L/s; glottal area: 0.065-1.76 cm(2); and glottal perimeter: 1.09-6.55 cm. Hyperfunctional whisper tended to have higher subglottal pressures and lower areas and flows than hypofunctional whisper, with neutral and postphonation whisper values in between. An important finding is that glottal flow changed more for small changes of area when the area was already small, and did not create much flow change when area was changed for already larger areas; that is, whisper is "more sensitive" to airflow changes for smaller glottal areas. A general equation for whisper aerodynamics was obtained, namely, P (subglottal pressure [cm H2O]) = C x F (glottal flow [cm(3)/s]), where C = 0.052 x A(4) - 0.1913 x A(3) + 0.2577 x A(2) - 0.1523 x A + 0.0388, where A is the glottal area (cm(2)). Another general equation for nondimensional terms (pressure coefficient vs Reynolds number) also is offered. Implications for whisper flow resistance and aerodynamic power are given. These results give insight into whisper aerodynamics and offer equations relevant to speech synthesis.
|
|
| 33. |
- Tuomi, Lisa, 1985, et al.
(författare)
-
Voice Outcome in Patients Treated for Laryngeal Cancer: Efficacy of Voice Rehabilitation.
- 2014
-
Ingår i: Journal of voice : official journal of the Voice Foundation. - : Elsevier BV. - 1873-4588. ; 28:1, s. 62-68
-
Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: To investigate the efficacy of voice rehabilitation regarding acoustically measured voice quality as well as self-perceived function after radiotherapy for laryngeal cancer. STUDY DESIGN: Prospective intervention study. METHODS: Twenty male patients irradiated for laryngeal cancer participated in the study. Voice recordings and self-assessment of voice function (hoarseness, vocal fatigue, and vocal loudness) were made one and 6 months after completion of radiotherapy. The recordings were analyzed with the program Praat. Ten of the patients received 10 sessions of structured voice rehabilitations between the recordings and 10 worked as a control group. RESULTS: Jitter and shimmer improved for both groups. Harmonics-to-noise-ratio and maximum phonation time improved for the patients who received voice rehabilitation while it deteriorated for the control group. The self-assessment questions about vocal fatigue and vocal loudness showed improvement for both groups while hoarseness showed no change. CONCLUSION: General improvement was seen for both the study group and the control group. Despite the lack of statistical significant difference, there are trends where greater improvement in perturbation and self-assessment measures are noted in the study group. The results suggest positive effects of voice rehabilitation in both voice quality and self-perceived function.
|
|
| 34. |
- Uloza, Virgilijus, et al.
(författare)
-
Categorizing Normal and Pathological Voices : Automated and Perceptual Categorization
- 2011
-
Ingår i: Journal of Voice. - New York : Mosby-Elsevier. - 0892-1997 .- 1873-4588. ; 25:6, s. 700-708
-
Tidskriftsartikel (refereegranskat)abstract
- Objectives: The aims of the present study were to evaluate the accuracy of an elaborated automated voice categorization system that classified voice signal samples into healthy and pathological classes and to compare it with classification accuracy that was attained by human experts. Material and Methods: We investigated the effectiveness of 10 different feature sets in the classification of voice recordings of the sustained phonation of the vowel sound /a/ into the healthy and two pathological voice classes, and proposed a new approach to building a sequential committee of support vector machines (SVMs) for the classification. By applying “genetic search” (a search technique used to find solutions to optimization problems), we determined the optimal values of hyper-parameters of the committee and the feature sets that provided the best performance. Four experienced clinical voice specialists who evaluated the same voice recordings served as experts. The “gold standard” for classification was clinically and histologically proven diagnosis. Results: A considerable improvement in the classification accuracy was obtained from the committee when compared with the single feature type-based classifiers. In the experimental investigations that were performed using 444 voice recordings coming from 148 subjects, three recordings from each subject, we obtained the correct classification rate (CCR) of over 92% when classifying into the healthy-pathological voice classes, and over 90% when classifying into three classes (healthy voice and two nodular or diffuse lesion voice classes). The CCR obtained from human experts was about 74% and 60%, respectively. Conclusion: When operating under the same experimental conditions, the automated voice discrimination technique based on sequential committee of SVM was considerably more effective than the human experts.
|
|
| 35. |
- Criaco, Giuseppe, et al.
(författare)
-
“To have and have not”: founders’ human capital and university start-up survival
- 2014
-
Ingår i: Journal of Technology Transfer. - : Springer. - 0892-9912 .- 1573-7047. ; 39:4, s. 567-593
-
Tidskriftsartikel (refereegranskat)abstract
- In order to preserve innovation, knowledge development and diffusion, as well as the transfer of new technologies, the emergence of University Start-Ups (USU) and their survival as a particular dimension of performance represents a relevant research topic. As USU generally have scarce initial resources, the human capital of their founders is one of their main business assets. Although the survival of such firms is supposed to be heavily dependent on the human capital characteristics of their founders, this has not received enough attention in existing research. In this paper we investigate the contribution of founders’ specific human capital characteristics to the survival of USU, building on Gimeno et al. (Adm Sci Q 42:750–783, 1997) threshold model of entrepreneurial exit. We divide USU founders’ specific human capital into three components (entrepreneurship, industry and university) in order to better understand its impact on firm survival. Our theoretical model is empirically tested on a unique sample of Catalan USU through a logistic regression analysis. Coherently with our theoretical reasoning, the results show that industry human capital negatively affect USU survival, while university human capital and entrepreneurship human capital enhance the likelihood of USU survival.
|
|
