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Acoustic Changes in Student Actors' Voices After 12 Months of Training
Acoustic Changes in Student Actors’ Voices After 12 Months of Training Peta Walzak, Patricia McCabe, Cate Madill, and Christine Sheard New South Wales, Australia
Summary: This study was to evaluate acoustic changes in student actors’ voices after 12 months of actor training. The design used was a longitudinal study. Eighteen students enrolled in an Australian tertiary 3-year acting program (nine male and nine female) were assessed at the beginning of their acting course and again 12 months later using a questionnaire, interview, maximum phonation time (MPT), reading, spontaneous speaking, sustained phonation tasks, and a pitch range task. Samples were analyzed for MPT, fundamental frequency across tasks, pitch range for speaking and reading, singing pitch range, noise-to-harmonic ratio, shimmer, and jitter. After training, measures of shimmer significantly increased for both male and female participants. Female participants’ pitch range significantly increased after training, with a significantly lower mean frequency for their lowest pitch. The finding of limited or negative changes for some measures indicate that further investigation is required into the long-term effects of actor voice training and which parameters of voicing are most targeted and valued in training. Particular investigation into the relationship between training targets and outcomes could more reliably inform acting programs about changes in teaching methodologies. Further research into the relationship between specific training techniques, physiological changes, and vocal changes may also provide information on implementing more evidence-based training methods. Key Words: Actor voice—Voice training.
minimum vocal effort.2 The actor also changes components of their voice such as volume and pitch to convey emotional expression in order to portray a character.3–5 The necessity of increasing volume, changing pitch, and extending frequency range beyond typical conversation would suggest that actors
INTRODUCTION The vocal requirements of acting differ from those of everyday conversation.1 Actors are required to use effective vocal projection, requiring an ability to produce a voice that is loud enough to hear in various performance spaces whilst using
Faculty of Health Sciences, The University of Sydney, Lidcombe, NSW 2141, Australia. E-mail: pwal0308@ mail.usyd.edu.au Journal of Voice, Vol. 22, No. 3, pp. 300–313 0892-1997/$34.00 Ó 2008 The Voice Foundation doi:10.1016/j.jvoice.2006.10.006
Accepted for publication October 9, 2006. Parts of this research were presented at the 7th Australian Voice Symposium, Sydney, Australia in September 2005. School of Communication Sciences & Disorders, University of Sydney, Australia. Address correspondence and reprint requests to Peta Walzak, School of Communication Sciences & Disorders,
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ACOUSTIC CHANGES IN STUDENT ACTORS’ VOICES need an efficient performance voice2 and the ability to maintain voice quality throughout their careers. Improvements have been reported after training for general measures of quality using the Dysphonia Severity Index6 and the Grade, Roughness, Breathiness, Asthenia, Strain (GRBAS) perceptual scale.7,8 Improvements in actors’ ability to modify the intensity of their voices without simultaneously making adjustments to frequency9 and use of a wider range of fundamental frequencies10 have also been reported after training. The general trend of these findings is for positive effects after actor training. Differences in subjects, sample size, design, and methodology make comparison between studies difficult, particularly with regard to length of training time and use of matched controls. Studies that compare trained and control groups vary considerably in relation to their findings of overall voice quality prior to training and to changes after training.8,10 The use of a variety of speech tasks and analysis of the same acoustic components for each task as opposed to analyzing different components of different tasks to evaluate changes made after training may also provide more specific information on what changes allow the actor to achieve most efficient voice and provide longevity of the voice. METHODS Participants The whole first year cohort (24 students) enrolled in an Australian 3-year acting degree were approached to participate in the research and all students agreed to participate. Of the 24 consenting students, 3 were excluded due to insufficient demographic information, and 3 were excluded due to insufficient or distorted acoustic samples. Participants (nine male and nine female) were between the ages of 19 and 31 years (mean age 5 22 years, standard deviation [SD] 5 3). Throughout the first year of their acting degrees, participants regularly attended daily group voice classes of 1 to 1½ hours duration over three terms of 16 weeks each. These voice classes mainly addressed breathing, with particular focus on the ‘‘diaphragm, clearing the passage through which sound travels and the forwardness of the sound into the
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mask of the face’’ (personal communication, head voice teacher, June 30, 2006). Aspects such as projection, stamina, and dialects are addressed in later years of the voice program. The fundamental aim of the entire voice program is to ‘‘free the natural voice’’ whilst also working to ‘‘get more body into it’’ (personal communication, head voice teacher, June 30, 2006). The approach used in this program is an eclectic one, which is predominately influenced by the methodologies of Berry11 and Rodenburg12 and takes a skill building focus rather than rigidly adhering to a prescribed theoretical curriculum. In discussing the voice program, the head teacher of voice described in class feedback to students as typically including comments such as ‘‘letting go,’’ ‘‘get it forward,’’ ‘‘open channel,’’ and ‘‘the more open everything is the richer the sound,’’ indicating feedback on outcome rather than feedback on technique. This correlates with the principles of motor learning feedback type of ‘‘knowledge of results’’13 and is suggestive of a master-apprentice approach to vocal technique acquisition. Participants also took classes in acting, movements, music, history of theatre, play production, and professional development. Screening protocol All participants were screened at the beginning of their acting course as part of a previous study looking at objective and perceptual measures of actor and non-actor voices.14 The second instance of data collection occurred after a year of acting training and the same protocol was used for both data collection points. The initial screening was conducted at the commencement of the course, with the second screening conducted at the commencement of the participant’s second academic year. At the time of the second screening, students had just completed a 6-week end-of-year break. All participants completed a questionnaire15 (Appendix A) that elicited information about demographics, medical history, vocal habits, voice training history, and employment. Each participant was then interviewed by the first author to explore any issues as identified in the questionnaire (Appendix B). Participants were asked to complete five vocal tasks. These tasks were maximum phonation time (MPT), a reading task, a spontaneous speaking Journal of Voice, Vol. 22, No. 3, 2008
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task, a sustained phonation task, and a pitch range singing task. All these components, ie, questionnaire, interview, and vocal tasks were conducted using the same protocol both at commencement of training and after 12-month training. All vocal tasks were digitally recorded using an AKG C420 Cardiod head mounted condenser microphone (AKG Acoustics GmbH, Vienna, Austria). The digital signal input was via an Edirol UA-5 24Bit 96 kHz USB Audio Interface onto an ASUS 2500H laptop computer. Each voice sample was recorded and saved as a digital file using Cool Edit Pro 1.2 (Adobe Systems Inc., San Jose, CA). MPT tasks were conducted twice, with the longest time being used for analysis. A 3-second segment of the MPT sustained vowel was selected commencing 2 seconds after the start of the vowel16 to provide data on shimmer, jitter, noise-to-harmonic ratio, and fundamental frequency. For the reading task, the Rainbow Passage17 was used and a segment of sentence three (‘‘and its two ends apparently beyond the horizon’’) was analyzed following the Morgan et al14 protocol. The reading task was considered to be a performance sample given evidence to suggest that actors often change the same components of voice for read and scripted passages when compared to spontaneous speech.9 For the spontaneous speech sample, participants were required to describe the Cookie Theft Picture for 1 minute.18 From the spontaneous speech task, a 10-second sample was taken commencing 5 seconds after the beginning of the sample. The speech excerpts from the reading and spontaneous speech samples were both analyzed for pitch range and fundamental frequency. For the singing pitch range task, participants were required to sing a continuous scale from the middle of their range to their highest note and the middle of their range down to their lowest note. The difference between these two measures was calculated to determine participants’ pitch range in both Hertz and semitones. The same verbal instructions were given to all subjects for the vocal tasks on both recording occasions. Each task segment was analyzed using the MultiDimensional Voice Program Advanced Speech analysis and the pitch range task was analyzed using the Real Time Pitch program (Kay Elemetrics, Computerized Speech Lab, Lincoln Park, NJ). Journal of Voice, Vol. 22, No. 3, 2008
Analysis This study was to investigate acoustic changes in participants’ voices after 12 months of actor training. Paired t tests were used to investigate differences in participants over time for the following measures: Fo speaking, speaking pitch range, Fo reading, reading pitch range, Fo sustained vowel, jitter percent (for sustained vowel), shimmer (for sustained vowel), noise to harmonic ratio (NHR) (for sustained vowel), singing pitch range, and MPT. These pitch range and perturbation measures are closely associated with the aims of the training program of ‘‘releasing the voice without using extraneous effort.’’ The Dysphonia Severity Index6 was also calculated for each participant to allow comparison across studies.8 The Dysphonia Severity Index6 calculates weighted measures for varying acoustic components to provide an overall quality rating6 and correlation of this score with the ‘‘G’’ score of the GRBAS7 scale has been made.6 Comparison of participants’ Dysphonia Severity Index6 was conducted using a matched pair t test. Data were analyzed according to gender due to differences in Fo, pitch range, and aerodynamic measures across genders.19,20 A Bonferroni correction was then applied to assess the robustness of a significant finding.21 In this study, a total of 18 matched pair t tests were conducted, yielding a Bonferroni corrected cut off for significance of P ! 0.0028 (0.05/18).
RESULTS Table 1 presents data for frequency variables in tasks across time for male participants. There was no significant difference for measures of frequency across the group over time. Table 2 presents data for frequency variables of female participants. The mean minimum frequency was significantly lower after training. There was no significant difference in measures of Fo for speaking, reading, or sustained vowel. There was a significant difference in the lowest pitch after training. Table 3 shows perturbation measures for male participants. Perturbation measures were taken form the sustained vowel sample. Shimmer measures showed a significant increase after training.
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TABLE 1. Frequency Variables for Male Participants Difference Difference Over Time t Test Over Time Commencement After 12 Months of Course (Time 1) Training (Time 2) (Time 1LTime 2) (Time 1LTime 2) (Matched Pair)
Fo speaking (Hz) Fo reading (Hz) Fo sustained vowel (Hz) Maximum frequency (Hz) Minimum frequency (Hz)
Mean
Mean
Mean
105.10 108.44 120.00 713.61 97.91
126.45 123.25 123.46 965.24 75.36
10.18 14.82 3.46 77.01 3.36
SD
P Value
16.87 16.42 31.76 79.35 16.89
0.05 0.01 0.38 0.03 0.01
Note: Following the Bonferroni correction the t test results were considered statistically significant if P ! 0.0028.
Changes in jitter and NHR were not significant after training. Table 4 shows measures of perturbation for female participants. Shimmer showed a highly significant change after training, with an increased measure of shimmer. There was no significant difference for the measures of jitter and NHR across time. Table 5 presents changes in pitch range for male participants after training. There was no significant change in the pitch range used across tasks. Table 6 shows pitch range data for female participants. There was a significant increase in the singing pitch range after training. There was no significant change in pitch range after training for speaking and reading tasks. Table 7 shows the MPT for male and female participants. There was no significant change in this measure after training for either group. Table 8 shows the results for Dysphonia Severity Index6 for male and female participants and shows no significant change for either group after 12 months of training.
Given the multiple number of comparisons made, a Bonferroni correction was conducted. A number of measures would have shown significant levels of change if this correction had not been made. This correction was made to reduce the likelihood of reporting false positives.21 DISCUSSION The aim of this study was to measure the acoustic changes in acting students’ voices after a period of 12 months of actor training. Previous studies into actor training and voice change have followed acting students over a shorter period of time9,22 or have conducted acoustic and aerodynamic analysis on limited tasks (ie, sustained vowel only).8 A significant increase in singing pitch range for female participants was seen after 12 months of training. This increase in range is consistent with prior findings.9 Although a significant increase in male participants’ range was not seen, there was an increase in pitch range that approached
TABLE 2. Frequency Variables for Female Participants
Fo speaking (Hz) Fo reading (Hz) Fo sustained vowel (Hz) Maximum frequency (Hz) Minimum frequency (Hz)
Commencement of Course
After 12 Months Training
Difference Over Time (Time 1LTime 2)
Difference Over Time (Time 1LTime 2)
t Test (Matched Pair)
Mean
Mean
Mean
SD
P Value
191.71 196.30 210.65 813.87 144.733
205.21 204.77 207.39 991.29 94.67
13.50 8.47 3.26 177.42 50.06
11.98 31.78 28.00 278.38 35.97
0.005 0.22 0.37 0.046 0.002
Note: Following the Bonferroni correction the t test results were considered statistically significant if P ! 0.0028. Journal of Voice, Vol. 22, No. 3, 2008
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PETA WALZAK ET AL TABLE 3. Perturbation Variables for Male Participants
Jitter (%) Shimmer (dB) NHR
Commencement of Course
After 12 Months Training
Difference Over Time (Time 1LTime 2)
Difference Over Time (Time 1LTime 2)
t Test (Matched Pair)
Mean
Mean
Mean
SD
P Value
1.06 0.27 0.12
0.73 2.96 0.13
0.33 2.69 0.01
0.52 1.57 0.03
0.05 0.0004 0.16
Note: Following the Bonferroni correction the t test results were considered statistically significant if P ! 0.0028.
significance. For male participants, the change in range over time was seen in both maximum and minimum frequencies. However, the female participants increase in pitch range was achieved more in the lower frequencies. The female participants were evaluated at commencement of training and compared with a matched control population and had significantly lower speaking fundamental frequency than controls.14 Given that these female participants demonstrated increased levels of shimmer after training, the difference in their fundamental frequency raises questions about the relationship between mechanisms of pitch lowering and voice quality and the link between vocal disorder and lower fundamental frequency.23,24 The relationship between use of a lower pitch and glottic closure also warrants further investigation due to the link with vocal fatigue and inefficient voicing.24 The other consideration is that the significant change in the lowest frequency that the participants used may be related to the theatre voice-training methodologies. This increase in range is consistent with the aim of the voice program of ‘‘freeing the natural voice’’ and the idea of
obtaining a ‘‘voice that is extremely flexible’’ (personal communication with head voice teacher, 30 June 2006). However, as previous research did not report on whether pitch range increased for higher, lower, or both frequencies9 further investigation is needed to determine if this is an artifact of actor voice training. The significantly increased measures of shimmer after training for both groups of participants is unexpected as previous studies have shown general trends of improved voice quality.9,10 The approach used in the voice program, predominately Berry11 and Rodenburg,12 suggests that increased measures of shimmer would not be expected as students are taught how to ‘‘free’’ their voice in an effortless manner. The increase in levels of shimmer is also unexpected as the measures after training are higher than for a general population.25 The increase of shimmer alone (and not jitter) is also unusual indicating participants were able to maintain a more regular pattern of vocal fold vibration, while the control of the intensity varied. This may be the result of increased effort for this task and difficulty in using a stable projected voice. Although the
TABLE 4. Perturbation Variables for Female Participants
Jitter (%) Shimmer (dB) NHR
Commencement of Course
After 12 months Training
Difference Over Time (Time 1LTime 2)
Difference Over Time (Time 1LTime 2)
t Test (Matched Pair)
Mean
Mean
Mean
SD
P Value
0.46 0.18 0.12
0.95 2.21 0.11
0.49 2.03 0.01
0.72 0.62 0.02
0.04 0.000005 0.04
Note: Following the Bonferroni correction the t test results were considered statistically significant if P ! 0.0028. Journal of Voice, Vol. 22, No. 3, 2008
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TABLE 5. Pitch Range Variables for Male Participants Commencement of Course (Time 1)
Speaking pitch range (semitones) Reading pitch range (semitones) Singing pitch range (semitones)
Difference Difference After 12 Months Over Time t Test Over Time Training (Time 1LTime 2) (Time 1LTime 2) (Matched Pair) (Time 2)
Mean
Mean
Mean
SD
P Value
30.78 15.67 35.67
19.33 16 43.78
11.44 0.33 8.11
17.14 8.73 7.44
0.04 0.46 0.006
Note: Following the Bonferroni correction the t test results were considered statistically significant if P ! 0.0028.
training methods used in this program focus on using an ‘‘open’’ sound with released effort, the students may not yet have mastered the skill of producing this voice quality without effort. This finding of a negative change in perturbation raises further questions about the nature of this population. Poor voice quality has previously been found in acting students.26 Given actors’ lifestyle, the vocal load of training and performance,26 or the use of performance-related vocally abusive behaviors4 this finding of increased shimmer may be related to the fact that this population typically engages in vocally damaging behaviors.26 The finding of no significant changes in measures on the Dysphonia Severity Index6 contradicts Timmermans et al’s8 findings. However, measures in this study were over 12 months of training when compared to 18 months in Timmermans et al.8 It is possible that some measures of voice show change over longer training periods and continued longitudinal study is planned.
The finding of no significant change in measures of fundamental frequency across tasks for both male and female participants is inconsistent with the results of Feudo et al.9 Previously, increased measures of fundamental frequency have been found in reading tasks and these changes have been similar to changes of fundamental frequency for rehearsed script.9 The result of no significant change in reading fundamental frequency may indicate that students did not use a performance like quality when reading. Considering the participants had recently returned from a 6-week break, were not participating in voice training or any additional rehearsals or performances, these findings are unexpected. Having completed the first year of a 3-year acting course, it is likely that the demands placed on their voice exceeded the vocal demands at commencement of their acting program. Actors often exceed their voice range profile,27 or have vocal limitations for optimal voice efficiency, when performing.27
TABLE 6. Pitch Range Variables for Female Participants
Speaking pitch range (semitones) Reading pitch range (semitones) Singing pitch range (semitones)
Commencement of Course
After 12 Months Training
Difference Over Time (Time 1LTime 2)
Difference Over Time (Time 1LTime 2)
t Test (Matched Pair)
Mean
Mean
Mean
SD
P Value
23.44
23.44
0
11.80
0.5
13.67
16.67
3
4.15
0.03
30.56
49
6.31
0.00001
18.44
Note: Following the Bonferroni correction the t test results were considered statistically significant if P ! 0.0028. Journal of Voice, Vol. 22, No. 3, 2008
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PETA WALZAK ET AL TABLE 7. MPT for Male and Female Participants Commencement of Course (Time 1)
After 12 Months Training (Time 2)
Difference Over Time (Time 1LTime 2)
Difference Over Time (Time 1LTime 2)
t Test (Matched Pair)
Mean
Mean
Mean
SD
P Value
23 16
19.56 13.56
3.44 2.44
3.56 4.03
0.12 0.05
Male MPT (seconds) Female MPT (seconds)
Note: Following the Bonferroni correction the t test results were considered statistically significant if P ! 0.0028.
Emerich et al27 hypothesized that a limited intensity and pitch range exist for any individual’s voice and that exceeding this range can damage laryngeal tissue, resulting in reduced vocal efficiency and vocal fatigue. Little has been reported on the efficacy of specific training to assist an individual in using their most efficient range, or of specific measures ideal for determining an individual’s range. The finding of limited change and or negative changes in the actors’ voices after training may also be indicative of a negative effect of training. This negative finding raises questions about optimal training methods and how best to monitor the voices of individual actors.28 Although some of these findings were similar to those seen in previous studies9 the limited change and many differences compared to other studies8,9 raise questions about length and different methods of voice training for actors as well as the relationship between changes in voice quality and vocal training. This study suggests that the extension of the female participants’ pitch range into lower frequencies and their significantly increased vocal shimmer post training may be related. TABLE 8. Dysphonia Severity Index6 for Male and Female Participants Commencement of Training
Male DSI Female DSI
After 12 Months Training
t Test (Matched Pair)
Mean
SD
Mean
SD
P Value
1.24 1.45
2.42 1.19
0.63 1.17
1.85 1.61
0.17 0.29
Note: Following the Bonferroni correction the t test results were considered statistically significant if P ! 0.0028. Abbreviation: DSI, dysphonia severity index. Journal of Voice, Vol. 22, No. 3, 2008
CONCLUSION This longitudinal study evaluated changes in objective measures in acting students’ voices after 12 months of training. There was a significant increase in shimmer levels after 12 months for all participants. There was also a significant increase in female participants’ singing pitch range and a reduction in their lowest mean singing pitch after training. Many acoustic measures did not change after training, and some measures that did change were negative changes. This indicated that after training, the actors’ voices in the testing situation had either not improved, or had even worsened for some components. Further evaluation of these negative changes may inform possible improvements in training methods to assist actors in achieving optimal use of their voice. Further investigation into training effects over a longer period may assist in determining amount or length of training needed and the relationship/s between vocal changes. Investigation into the relationship between acoustic changes, physiological changes, and training may also benefit development of improved training methods. Perceptual evaluation may also assist in measuring training effects.
REFERENCES 1. Harvey P, Feudo P, Aronson D. Objective analysis of actors’ voices: an initial report. J Voice. 1989;3:143–147. 2. Pinczower R, Oates J. Vocal projection in actors: the longterm average spectral features that distinguish comfortable acting voice from voicing with maximal projection in male actors. J Voice. 2005;19:440–453. 3. Acker BF. Vocal tract adjustments for the projected voice. J Voice. 1987;1:77–82.
ACOUSTIC CHANGES IN STUDENT ACTORS’ VOICES 4. Roy N, Ryker K, Bless D. Vocal violence in actors: an investigation into its acoustic consequences and the effects of hygienic laryngeal release training. J Voice. 2000;14:215–230. 5. Scherer K. Vocal measurement of emotion. In: Plutchik R, Kellerman H, eds, Emotion: Theory, Research, and Experience, Vol 4. San Diego: Academic Press; 1989:233–259. 6. Wuyts F, De Bodt M, Molenberghs G, et al. The Dysphonia Severity Index Scale: an objective measure of vocal quality based on a multiparameter approach. J Speech Lang Hear Res. 2000;43:796–809. 7. Hirano M. Clinical applications of voice tests. Assessment of Speech and Voice Production. Bethesda, MD: NIDCD; 1990:196–203. 8. Timmermans B, De Bodt M, Wuyts F, Van de Heyning P. Training outcomes in future professional voice users after 18 months of voice training. Folia Phoniatr Logop. 2004; 56:120–129. 9. Feudo P, Harvey P, Aronson D. Objective analysis of actors voices—comparative development across training. J Voice. 1992;6:267–270. 10. Kovacic G, Budanovac A. Acoustic characteristic of adolescent actors’ voices and non-actors’ voices. Folia Phoniatr Logop. 2000;54:125–132. 11. Berry C. Your Voice, and How to Use it Successfully. London: Harrap; 1993. 12. Rodenburg P. The Right to Speak: Working with the Voice. London: Methuen Drama; 1992. 13. Duffy J. Motor Speech Disorders. 2nd ed. Missouri: Elsevier Mosby; 2005. 14. Morgan, P, McCabe, P, Madill, C. Do acting students have the same voice qualities as non-acting students? Poster presented to the International Association of Logopaedics and Phoniatrics (IALP) Congress, Brisbane, Australia; 2004. 15. Cusiter J. Dysphonia related to inhaled corticosteroid treatment in asthma: Effects of dosage reduction. Unpublished Honours thesis, University of Sydney, Sydney; 2004.
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16. Brown W, Rothman H, Sapienza C. Perceptual and acoustic study of professionally trained versus untrained voices. J Voice. 2000;12:301–309. 17. Fairbanks G. Voice and Articulation Drill Book. New York: Harper & Row; 1960. 18. Goodglass H, Kaplan E, Barresi B. Boston Diagnostic Aphasia Examination. 3rd ed. Philadelphia, PA: Lippincott, Williams & Wilkins; 2001. 19. Goozee J, Murdoch B, Theodoros D, Thompson E. The effects of age and gender on laryngeal aerodynamics. Int J Lang Commun Disord. 1998;33:221–238. 20. Mathieson L. Greene and Mathieson’s: The voice and its disorders. 6th ed. London: Whurr; 2001. 21. Perneger T. What is wrong with Bonferroni adjustments. Br Med J. 1998;136:1236–1238. 22. Raphael B, Scherer R. Voice modifications of stage actors: acoustic analyses. J Voice. 1987;1:83–87. 23. Cooper M. Spectrographic analyses of fundamental frequency and hoarseness before and after vocal rehabilitation. J Speech Hear Disord. 1974;39:286–297. 24. Koufman J, Blalock PD. Vocal fatigue and dysphonia in the professional voice user: Bogart-Bacall syndrome. Laryngoscope. 1998;98:493–499. 25. Colton R, Casper J, Hirano M. Understanding Voice Problems: A Physiological Perspective for Diagnosis and Treatment. 2nd ed. Baltimore: Lippincott Williams & Wilkins; 1996. 26. Timmermans B. Poor voice quality in future elite vocal performers and professional voice users. J Voice. 2002; 16:372–382. 27. Emerich K, Titze I, Svec J, Popolo P, Logan G. Vocal range and intensity in actors: a studio versus stage comparison. J Voice. 2005;19:78–83. 28. Reid, KLP. An investigation of theatre voice training (based on the Linklater method). Unpublished PhD thesis, University of Sydney; 2003.
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PETA WALZAK ET AL APPENDIX A
Voice Qualities of Actors Voice Questionnaire Based on Sataloff, 1998 Subject Number __________________
Date ______/______/_______
Age _________
Height ___________________
Sex _________
Weight ___________________
Occupation _____________________________________ (1) How much do you use your voice at work every day: (please circle) 1–2 hours
2–4 hours
4–6 hours
6–8 hours
more than 8 hours
(2) Do you use a loud voice at work? Yes/No (3) Do you use a loud voice at home? Yes/No (4) Have you ever had training for your speaking or singing voice? Yes/No If “yes” please provide details (for how long, where, what kind of training): _________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ (5) How much sleep do you get (on average) every night: less than 4 hours
4–6 hours
6–8 hours
8–10 hours
more than 10 hours
(6) Do you exercise regularly? Yes/No If “yes” please give details:________________________________________________________ ______________________________________________________________________________ (7) How much alcohol do you drink? ______________________________________________________________________________ ______________________________________________________________________________
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(8) How many cups of coffee, tea, cola, or other caffeine-containing drinks do you drink per day? ______________________________________________________________________________ ______________________________________________________________________________ (9) Have you ever smoked? Yes/No If “yes” please provide details (for how long, how many, how long since you quit):___________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ (10) Do you live or work in a smoky environment? Yes/No If “yes” please give details:________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ (11) List any other recreational drugs you use: ______________________________________________________________________________ ______________________________________________________________________________ (12) Have you noticed any of the following in the last 6 months? (please tick all that apply) Voice worse in the morning Voice worse later in the day, after it has been used Frequently clear your throat Frequently experience sore throat / sensation in the throat Jaw joint problems Bitter or acid taste; bad breath in the morning Frequent “heartburn” or hiatus hernia Frequent yelling or loud talking Frequent whispering Chronic fatigue/insomnia Work in dry or dusty conditions Eat late at night Ever used antacids Frequent bad breath Lived or worked around smoke or fumes If “yes” please give details: _________________________________________________ ______________________________________________________________________________ Frequently felt tired Work shift work Frequently thirsty/dehydrated Traveled recently: When _______________________________________________________ Where ________________________________________________________________________ (13) Have you noticed any changes in your voice in the last 6 months? Yes/No If “yes” please give details: _______________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ Journal of Voice, Vol. 22, No. 3, 2008
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(14) If “yes”, do you know what caused these changes? Yes/No If “yes” please give details:________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ (15) Did it come on slowly/suddenly? (circle one) (16) Is it getting worse/better/same (circle one) (17) Have you used your voice excessively (yelling/screaming) anytime over the last 6 months? Yes/No If “yes” please give details:_______________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ (18) Has any one commented on your voice? Yes/No If “yes” please give details:_______________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ (19) Have you experienced any of the following in the last 6 months? (Tick all that apply) Hoarseness (coarse or scratchy voice quality) Vocal fatigue (voice tires or changes quality after speaking for a short period of time) Difficulty speaking softly or loudly (circle which one applies) Loss of vocal range (high/low) Breathiness Tickling or choking sensation when speaking Pain in the throat when speaking Loss of voice Any other vocal difficulties/symptoms: _____________________________________________ ______________________________________________________________________________ ______________________________________________________________________________
(20) Have you noticed any of the following in the last 6 months? (Tick all that apply) Change in weight: gained/lost _____ kg in _____ weeks/months Excessive sweating Change in skin or hair Palpitation (fluttering) of the heart Numbness of the face or hands/feet Double vision / Blurred vision Confusion, dizziness,or loss of consciousness Difficulty with speech Difficulty with swallowing Journal of Voice, Vol. 22, No. 3, 2008
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Seizure (epileptic fit) Pain/stiffness in the neck or shoulder Shaking or tremors Memory change Personality change Hearing loss Ear pain Facial pain Lump in neck, face, or head Ear noises Nasal obstruction/deformity Nose bleeds
(21) Female subjects: Are you pregnant? Yes/No Are your menstrual periods regular? Yes/No Have you undergone a hysterectomy? Yes/No Were your ovaries removed? Yes/No Have you gone through menopause? Yes/No At what age did you reach puberty? __________ Are you currently menstruating? Yes/No Are you currently ovulating? Yes/No/Don’t know
(22) Male subjects: At what age did you reach puberty? _________ At what age did your voice break? __________
(23) All subjects: Have you suffered from any of the following in the last 6 months? (Tick all that apply) If “yes” please provide details: Cough (lasting more than 1 month) _______________________________________________ Bronchitis __________________________________________________________________ Sinusitis ____________________________________________________________________ Colds and/or flu ______________________________________________________________ Journal of Voice, Vol. 22, No. 3, 2008
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Allergies ___________________________________________________________________ Asthma ____________________________________________________________________ (24) Are you taking any medication for the above? Yes/No If “yes” please give details: _______________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ (25) Have you ever injured your head or neck? Yes/No If “yes” please give details:________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ (26) Have you been in any serious accidents? Yes/No If “yes” please give details:________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ (27) Have you experienced any heightened emotional situations in the last 6 months (eg, death of a loved one, stress at work, disagreement with family)? Yes/No If “yes” please give details:________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ (28) Have you experienced any heightened emotional situations in the last 24 hours? Yes/No If “yes” please give only basic details: _______________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ (29) Please tick any that apply to you TODAY: I feel tired/fatigued I am thirsty/dehydrated I feel anxious I feel depressed I feel angry I feel upset
Thank you for your time in filling out this questionnaire.
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APPENDIX B Voice Screening: The Interview Introduction: explain who you are, what’s going to happen, the format of today’s session Name, address, telephone number, age, DOB Any major voice symptoms, problems? (Describe; indicate severity); Sources? (eg, “Ok, maybe we could start off with just a few questions about your voice. Have you ever lost your voice? I mean, not just the odd bout of laryngitis. How long ago was that? Did it clear up all right? …Tell me what happens if you overdo the voice stuff? Do you notice anything? Does your voice ever give out on you? What happens when your voice is tired?) Eg, hoarse, husky or rough voice, reduced vocal range, pain in throat area
Explore potential risk factors as they arise (see below) Any problems with speech? (eg, articulation) Describe previous voice/speech training Health Upper respiratory tract symptoms—include description of severity of: - asthma; cough - excessive mucus production; chest/nasal airways (eg, postnasal drip) - sinusitis - bronchitis - allergies Ear infections, otitis media
Describe treatment sought (doctors, etc) and outcome List any medications used. Ask if taking any regular prescribed medication.
Describe current voice quality (eg, Is today good or bad?) Rough, clear, low pitched, high pitched, slightly hypernasal, phonation breaks, hyponasal, monotonous, breathy, strong, loud, rich, resonant, soft, etc. Make an observation about their voice (eg, “I notice that your voice as a slight rough edge to it. Is that how it is normally? It also seems quite low pitched. Has anyone commented to you about that?”)
Potential risk factors Loud talking, shouting, screaming Excessive voice use Tension Excessive singing Fast speech Throat clearing History of respiratory tract problems Hard glottal attack Speaking in loud background noise (eg, clubs) Smoking Excessive use of stimulants/diuretics Sore throat
Always remember to ask about - drinking - smoking - hearing Journal of Voice, Vol. 22, No. 3, 2008
Summary: This study was to evaluate acoustic changes in student actors’ voices after 12 months of actor training. The design used was a longitudinal study. Eighteen students enrolled in an Australian tertiary 3-year acting program (nine male and nine female) were assessed at the beginning of their acting course and again 12 months later using a questionnaire, interview, maximum phonation time (MPT), reading, spontaneous speaking, sustained phonation tasks, and a pitch range task. Samples were analyzed for MPT, fundamental frequency across tasks, pitch range for speaking and reading, singing pitch range, noise-to-harmonic ratio, shimmer, and jitter. After training, measures of shimmer significantly increased for both male and female participants. Female participants’ pitch range significantly increased after training, with a significantly lower mean frequency for their lowest pitch. The finding of limited or negative changes for some measures indicate that further investigation is required into the long-term effects of actor voice training and which parameters of voicing are most targeted and valued in training. Particular investigation into the relationship between training targets and outcomes could more reliably inform acting programs about changes in teaching methodologies. Further research into the relationship between specific training techniques, physiological changes, and vocal changes may also provide information on implementing more evidence-based training methods. Key Words: Actor voice—Voice training.
minimum vocal effort.2 The actor also changes components of their voice such as volume and pitch to convey emotional expression in order to portray a character.3–5 The necessity of increasing volume, changing pitch, and extending frequency range beyond typical conversation would suggest that actors
INTRODUCTION The vocal requirements of acting differ from those of everyday conversation.1 Actors are required to use effective vocal projection, requiring an ability to produce a voice that is loud enough to hear in various performance spaces whilst using
Faculty of Health Sciences, The University of Sydney, Lidcombe, NSW 2141, Australia. E-mail: pwal0308@ mail.usyd.edu.au Journal of Voice, Vol. 22, No. 3, pp. 300–313 0892-1997/$34.00 Ó 2008 The Voice Foundation doi:10.1016/j.jvoice.2006.10.006
Accepted for publication October 9, 2006. Parts of this research were presented at the 7th Australian Voice Symposium, Sydney, Australia in September 2005. School of Communication Sciences & Disorders, University of Sydney, Australia. Address correspondence and reprint requests to Peta Walzak, School of Communication Sciences & Disorders,
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ACOUSTIC CHANGES IN STUDENT ACTORS’ VOICES need an efficient performance voice2 and the ability to maintain voice quality throughout their careers. Improvements have been reported after training for general measures of quality using the Dysphonia Severity Index6 and the Grade, Roughness, Breathiness, Asthenia, Strain (GRBAS) perceptual scale.7,8 Improvements in actors’ ability to modify the intensity of their voices without simultaneously making adjustments to frequency9 and use of a wider range of fundamental frequencies10 have also been reported after training. The general trend of these findings is for positive effects after actor training. Differences in subjects, sample size, design, and methodology make comparison between studies difficult, particularly with regard to length of training time and use of matched controls. Studies that compare trained and control groups vary considerably in relation to their findings of overall voice quality prior to training and to changes after training.8,10 The use of a variety of speech tasks and analysis of the same acoustic components for each task as opposed to analyzing different components of different tasks to evaluate changes made after training may also provide more specific information on what changes allow the actor to achieve most efficient voice and provide longevity of the voice. METHODS Participants The whole first year cohort (24 students) enrolled in an Australian 3-year acting degree were approached to participate in the research and all students agreed to participate. Of the 24 consenting students, 3 were excluded due to insufficient demographic information, and 3 were excluded due to insufficient or distorted acoustic samples. Participants (nine male and nine female) were between the ages of 19 and 31 years (mean age 5 22 years, standard deviation [SD] 5 3). Throughout the first year of their acting degrees, participants regularly attended daily group voice classes of 1 to 1½ hours duration over three terms of 16 weeks each. These voice classes mainly addressed breathing, with particular focus on the ‘‘diaphragm, clearing the passage through which sound travels and the forwardness of the sound into the
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mask of the face’’ (personal communication, head voice teacher, June 30, 2006). Aspects such as projection, stamina, and dialects are addressed in later years of the voice program. The fundamental aim of the entire voice program is to ‘‘free the natural voice’’ whilst also working to ‘‘get more body into it’’ (personal communication, head voice teacher, June 30, 2006). The approach used in this program is an eclectic one, which is predominately influenced by the methodologies of Berry11 and Rodenburg12 and takes a skill building focus rather than rigidly adhering to a prescribed theoretical curriculum. In discussing the voice program, the head teacher of voice described in class feedback to students as typically including comments such as ‘‘letting go,’’ ‘‘get it forward,’’ ‘‘open channel,’’ and ‘‘the more open everything is the richer the sound,’’ indicating feedback on outcome rather than feedback on technique. This correlates with the principles of motor learning feedback type of ‘‘knowledge of results’’13 and is suggestive of a master-apprentice approach to vocal technique acquisition. Participants also took classes in acting, movements, music, history of theatre, play production, and professional development. Screening protocol All participants were screened at the beginning of their acting course as part of a previous study looking at objective and perceptual measures of actor and non-actor voices.14 The second instance of data collection occurred after a year of acting training and the same protocol was used for both data collection points. The initial screening was conducted at the commencement of the course, with the second screening conducted at the commencement of the participant’s second academic year. At the time of the second screening, students had just completed a 6-week end-of-year break. All participants completed a questionnaire15 (Appendix A) that elicited information about demographics, medical history, vocal habits, voice training history, and employment. Each participant was then interviewed by the first author to explore any issues as identified in the questionnaire (Appendix B). Participants were asked to complete five vocal tasks. These tasks were maximum phonation time (MPT), a reading task, a spontaneous speaking Journal of Voice, Vol. 22, No. 3, 2008
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task, a sustained phonation task, and a pitch range singing task. All these components, ie, questionnaire, interview, and vocal tasks were conducted using the same protocol both at commencement of training and after 12-month training. All vocal tasks were digitally recorded using an AKG C420 Cardiod head mounted condenser microphone (AKG Acoustics GmbH, Vienna, Austria). The digital signal input was via an Edirol UA-5 24Bit 96 kHz USB Audio Interface onto an ASUS 2500H laptop computer. Each voice sample was recorded and saved as a digital file using Cool Edit Pro 1.2 (Adobe Systems Inc., San Jose, CA). MPT tasks were conducted twice, with the longest time being used for analysis. A 3-second segment of the MPT sustained vowel was selected commencing 2 seconds after the start of the vowel16 to provide data on shimmer, jitter, noise-to-harmonic ratio, and fundamental frequency. For the reading task, the Rainbow Passage17 was used and a segment of sentence three (‘‘and its two ends apparently beyond the horizon’’) was analyzed following the Morgan et al14 protocol. The reading task was considered to be a performance sample given evidence to suggest that actors often change the same components of voice for read and scripted passages when compared to spontaneous speech.9 For the spontaneous speech sample, participants were required to describe the Cookie Theft Picture for 1 minute.18 From the spontaneous speech task, a 10-second sample was taken commencing 5 seconds after the beginning of the sample. The speech excerpts from the reading and spontaneous speech samples were both analyzed for pitch range and fundamental frequency. For the singing pitch range task, participants were required to sing a continuous scale from the middle of their range to their highest note and the middle of their range down to their lowest note. The difference between these two measures was calculated to determine participants’ pitch range in both Hertz and semitones. The same verbal instructions were given to all subjects for the vocal tasks on both recording occasions. Each task segment was analyzed using the MultiDimensional Voice Program Advanced Speech analysis and the pitch range task was analyzed using the Real Time Pitch program (Kay Elemetrics, Computerized Speech Lab, Lincoln Park, NJ). Journal of Voice, Vol. 22, No. 3, 2008
Analysis This study was to investigate acoustic changes in participants’ voices after 12 months of actor training. Paired t tests were used to investigate differences in participants over time for the following measures: Fo speaking, speaking pitch range, Fo reading, reading pitch range, Fo sustained vowel, jitter percent (for sustained vowel), shimmer (for sustained vowel), noise to harmonic ratio (NHR) (for sustained vowel), singing pitch range, and MPT. These pitch range and perturbation measures are closely associated with the aims of the training program of ‘‘releasing the voice without using extraneous effort.’’ The Dysphonia Severity Index6 was also calculated for each participant to allow comparison across studies.8 The Dysphonia Severity Index6 calculates weighted measures for varying acoustic components to provide an overall quality rating6 and correlation of this score with the ‘‘G’’ score of the GRBAS7 scale has been made.6 Comparison of participants’ Dysphonia Severity Index6 was conducted using a matched pair t test. Data were analyzed according to gender due to differences in Fo, pitch range, and aerodynamic measures across genders.19,20 A Bonferroni correction was then applied to assess the robustness of a significant finding.21 In this study, a total of 18 matched pair t tests were conducted, yielding a Bonferroni corrected cut off for significance of P ! 0.0028 (0.05/18).
RESULTS Table 1 presents data for frequency variables in tasks across time for male participants. There was no significant difference for measures of frequency across the group over time. Table 2 presents data for frequency variables of female participants. The mean minimum frequency was significantly lower after training. There was no significant difference in measures of Fo for speaking, reading, or sustained vowel. There was a significant difference in the lowest pitch after training. Table 3 shows perturbation measures for male participants. Perturbation measures were taken form the sustained vowel sample. Shimmer measures showed a significant increase after training.
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TABLE 1. Frequency Variables for Male Participants Difference Difference Over Time t Test Over Time Commencement After 12 Months of Course (Time 1) Training (Time 2) (Time 1LTime 2) (Time 1LTime 2) (Matched Pair)
Fo speaking (Hz) Fo reading (Hz) Fo sustained vowel (Hz) Maximum frequency (Hz) Minimum frequency (Hz)
Mean
Mean
Mean
105.10 108.44 120.00 713.61 97.91
126.45 123.25 123.46 965.24 75.36
10.18 14.82 3.46 77.01 3.36
SD
P Value
16.87 16.42 31.76 79.35 16.89
0.05 0.01 0.38 0.03 0.01
Note: Following the Bonferroni correction the t test results were considered statistically significant if P ! 0.0028.
Changes in jitter and NHR were not significant after training. Table 4 shows measures of perturbation for female participants. Shimmer showed a highly significant change after training, with an increased measure of shimmer. There was no significant difference for the measures of jitter and NHR across time. Table 5 presents changes in pitch range for male participants after training. There was no significant change in the pitch range used across tasks. Table 6 shows pitch range data for female participants. There was a significant increase in the singing pitch range after training. There was no significant change in pitch range after training for speaking and reading tasks. Table 7 shows the MPT for male and female participants. There was no significant change in this measure after training for either group. Table 8 shows the results for Dysphonia Severity Index6 for male and female participants and shows no significant change for either group after 12 months of training.
Given the multiple number of comparisons made, a Bonferroni correction was conducted. A number of measures would have shown significant levels of change if this correction had not been made. This correction was made to reduce the likelihood of reporting false positives.21 DISCUSSION The aim of this study was to measure the acoustic changes in acting students’ voices after a period of 12 months of actor training. Previous studies into actor training and voice change have followed acting students over a shorter period of time9,22 or have conducted acoustic and aerodynamic analysis on limited tasks (ie, sustained vowel only).8 A significant increase in singing pitch range for female participants was seen after 12 months of training. This increase in range is consistent with prior findings.9 Although a significant increase in male participants’ range was not seen, there was an increase in pitch range that approached
TABLE 2. Frequency Variables for Female Participants
Fo speaking (Hz) Fo reading (Hz) Fo sustained vowel (Hz) Maximum frequency (Hz) Minimum frequency (Hz)
Commencement of Course
After 12 Months Training
Difference Over Time (Time 1LTime 2)
Difference Over Time (Time 1LTime 2)
t Test (Matched Pair)
Mean
Mean
Mean
SD
P Value
191.71 196.30 210.65 813.87 144.733
205.21 204.77 207.39 991.29 94.67
13.50 8.47 3.26 177.42 50.06
11.98 31.78 28.00 278.38 35.97
0.005 0.22 0.37 0.046 0.002
Note: Following the Bonferroni correction the t test results were considered statistically significant if P ! 0.0028. Journal of Voice, Vol. 22, No. 3, 2008
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PETA WALZAK ET AL TABLE 3. Perturbation Variables for Male Participants
Jitter (%) Shimmer (dB) NHR
Commencement of Course
After 12 Months Training
Difference Over Time (Time 1LTime 2)
Difference Over Time (Time 1LTime 2)
t Test (Matched Pair)
Mean
Mean
Mean
SD
P Value
1.06 0.27 0.12
0.73 2.96 0.13
0.33 2.69 0.01
0.52 1.57 0.03
0.05 0.0004 0.16
Note: Following the Bonferroni correction the t test results were considered statistically significant if P ! 0.0028.
significance. For male participants, the change in range over time was seen in both maximum and minimum frequencies. However, the female participants increase in pitch range was achieved more in the lower frequencies. The female participants were evaluated at commencement of training and compared with a matched control population and had significantly lower speaking fundamental frequency than controls.14 Given that these female participants demonstrated increased levels of shimmer after training, the difference in their fundamental frequency raises questions about the relationship between mechanisms of pitch lowering and voice quality and the link between vocal disorder and lower fundamental frequency.23,24 The relationship between use of a lower pitch and glottic closure also warrants further investigation due to the link with vocal fatigue and inefficient voicing.24 The other consideration is that the significant change in the lowest frequency that the participants used may be related to the theatre voice-training methodologies. This increase in range is consistent with the aim of the voice program of ‘‘freeing the natural voice’’ and the idea of
obtaining a ‘‘voice that is extremely flexible’’ (personal communication with head voice teacher, 30 June 2006). However, as previous research did not report on whether pitch range increased for higher, lower, or both frequencies9 further investigation is needed to determine if this is an artifact of actor voice training. The significantly increased measures of shimmer after training for both groups of participants is unexpected as previous studies have shown general trends of improved voice quality.9,10 The approach used in the voice program, predominately Berry11 and Rodenburg,12 suggests that increased measures of shimmer would not be expected as students are taught how to ‘‘free’’ their voice in an effortless manner. The increase in levels of shimmer is also unexpected as the measures after training are higher than for a general population.25 The increase of shimmer alone (and not jitter) is also unusual indicating participants were able to maintain a more regular pattern of vocal fold vibration, while the control of the intensity varied. This may be the result of increased effort for this task and difficulty in using a stable projected voice. Although the
TABLE 4. Perturbation Variables for Female Participants
Jitter (%) Shimmer (dB) NHR
Commencement of Course
After 12 months Training
Difference Over Time (Time 1LTime 2)
Difference Over Time (Time 1LTime 2)
t Test (Matched Pair)
Mean
Mean
Mean
SD
P Value
0.46 0.18 0.12
0.95 2.21 0.11
0.49 2.03 0.01
0.72 0.62 0.02
0.04 0.000005 0.04
Note: Following the Bonferroni correction the t test results were considered statistically significant if P ! 0.0028. Journal of Voice, Vol. 22, No. 3, 2008
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TABLE 5. Pitch Range Variables for Male Participants Commencement of Course (Time 1)
Speaking pitch range (semitones) Reading pitch range (semitones) Singing pitch range (semitones)
Difference Difference After 12 Months Over Time t Test Over Time Training (Time 1LTime 2) (Time 1LTime 2) (Matched Pair) (Time 2)
Mean
Mean
Mean
SD
P Value
30.78 15.67 35.67
19.33 16 43.78
11.44 0.33 8.11
17.14 8.73 7.44
0.04 0.46 0.006
Note: Following the Bonferroni correction the t test results were considered statistically significant if P ! 0.0028.
training methods used in this program focus on using an ‘‘open’’ sound with released effort, the students may not yet have mastered the skill of producing this voice quality without effort. This finding of a negative change in perturbation raises further questions about the nature of this population. Poor voice quality has previously been found in acting students.26 Given actors’ lifestyle, the vocal load of training and performance,26 or the use of performance-related vocally abusive behaviors4 this finding of increased shimmer may be related to the fact that this population typically engages in vocally damaging behaviors.26 The finding of no significant changes in measures on the Dysphonia Severity Index6 contradicts Timmermans et al’s8 findings. However, measures in this study were over 12 months of training when compared to 18 months in Timmermans et al.8 It is possible that some measures of voice show change over longer training periods and continued longitudinal study is planned.
The finding of no significant change in measures of fundamental frequency across tasks for both male and female participants is inconsistent with the results of Feudo et al.9 Previously, increased measures of fundamental frequency have been found in reading tasks and these changes have been similar to changes of fundamental frequency for rehearsed script.9 The result of no significant change in reading fundamental frequency may indicate that students did not use a performance like quality when reading. Considering the participants had recently returned from a 6-week break, were not participating in voice training or any additional rehearsals or performances, these findings are unexpected. Having completed the first year of a 3-year acting course, it is likely that the demands placed on their voice exceeded the vocal demands at commencement of their acting program. Actors often exceed their voice range profile,27 or have vocal limitations for optimal voice efficiency, when performing.27
TABLE 6. Pitch Range Variables for Female Participants
Speaking pitch range (semitones) Reading pitch range (semitones) Singing pitch range (semitones)
Commencement of Course
After 12 Months Training
Difference Over Time (Time 1LTime 2)
Difference Over Time (Time 1LTime 2)
t Test (Matched Pair)
Mean
Mean
Mean
SD
P Value
23.44
23.44
0
11.80
0.5
13.67
16.67
3
4.15
0.03
30.56
49
6.31
0.00001
18.44
Note: Following the Bonferroni correction the t test results were considered statistically significant if P ! 0.0028. Journal of Voice, Vol. 22, No. 3, 2008
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PETA WALZAK ET AL TABLE 7. MPT for Male and Female Participants Commencement of Course (Time 1)
After 12 Months Training (Time 2)
Difference Over Time (Time 1LTime 2)
Difference Over Time (Time 1LTime 2)
t Test (Matched Pair)
Mean
Mean
Mean
SD
P Value
23 16
19.56 13.56
3.44 2.44
3.56 4.03
0.12 0.05
Male MPT (seconds) Female MPT (seconds)
Note: Following the Bonferroni correction the t test results were considered statistically significant if P ! 0.0028.
Emerich et al27 hypothesized that a limited intensity and pitch range exist for any individual’s voice and that exceeding this range can damage laryngeal tissue, resulting in reduced vocal efficiency and vocal fatigue. Little has been reported on the efficacy of specific training to assist an individual in using their most efficient range, or of specific measures ideal for determining an individual’s range. The finding of limited change and or negative changes in the actors’ voices after training may also be indicative of a negative effect of training. This negative finding raises questions about optimal training methods and how best to monitor the voices of individual actors.28 Although some of these findings were similar to those seen in previous studies9 the limited change and many differences compared to other studies8,9 raise questions about length and different methods of voice training for actors as well as the relationship between changes in voice quality and vocal training. This study suggests that the extension of the female participants’ pitch range into lower frequencies and their significantly increased vocal shimmer post training may be related. TABLE 8. Dysphonia Severity Index6 for Male and Female Participants Commencement of Training
Male DSI Female DSI
After 12 Months Training
t Test (Matched Pair)
Mean
SD
Mean
SD
P Value
1.24 1.45
2.42 1.19
0.63 1.17
1.85 1.61
0.17 0.29
Note: Following the Bonferroni correction the t test results were considered statistically significant if P ! 0.0028. Abbreviation: DSI, dysphonia severity index. Journal of Voice, Vol. 22, No. 3, 2008
CONCLUSION This longitudinal study evaluated changes in objective measures in acting students’ voices after 12 months of training. There was a significant increase in shimmer levels after 12 months for all participants. There was also a significant increase in female participants’ singing pitch range and a reduction in their lowest mean singing pitch after training. Many acoustic measures did not change after training, and some measures that did change were negative changes. This indicated that after training, the actors’ voices in the testing situation had either not improved, or had even worsened for some components. Further evaluation of these negative changes may inform possible improvements in training methods to assist actors in achieving optimal use of their voice. Further investigation into training effects over a longer period may assist in determining amount or length of training needed and the relationship/s between vocal changes. Investigation into the relationship between acoustic changes, physiological changes, and training may also benefit development of improved training methods. Perceptual evaluation may also assist in measuring training effects.
REFERENCES 1. Harvey P, Feudo P, Aronson D. Objective analysis of actors’ voices: an initial report. J Voice. 1989;3:143–147. 2. Pinczower R, Oates J. Vocal projection in actors: the longterm average spectral features that distinguish comfortable acting voice from voicing with maximal projection in male actors. J Voice. 2005;19:440–453. 3. Acker BF. Vocal tract adjustments for the projected voice. J Voice. 1987;1:77–82.
ACOUSTIC CHANGES IN STUDENT ACTORS’ VOICES 4. Roy N, Ryker K, Bless D. Vocal violence in actors: an investigation into its acoustic consequences and the effects of hygienic laryngeal release training. J Voice. 2000;14:215–230. 5. Scherer K. Vocal measurement of emotion. In: Plutchik R, Kellerman H, eds, Emotion: Theory, Research, and Experience, Vol 4. San Diego: Academic Press; 1989:233–259. 6. Wuyts F, De Bodt M, Molenberghs G, et al. The Dysphonia Severity Index Scale: an objective measure of vocal quality based on a multiparameter approach. J Speech Lang Hear Res. 2000;43:796–809. 7. Hirano M. Clinical applications of voice tests. Assessment of Speech and Voice Production. Bethesda, MD: NIDCD; 1990:196–203. 8. Timmermans B, De Bodt M, Wuyts F, Van de Heyning P. Training outcomes in future professional voice users after 18 months of voice training. Folia Phoniatr Logop. 2004; 56:120–129. 9. Feudo P, Harvey P, Aronson D. Objective analysis of actors voices—comparative development across training. J Voice. 1992;6:267–270. 10. Kovacic G, Budanovac A. Acoustic characteristic of adolescent actors’ voices and non-actors’ voices. Folia Phoniatr Logop. 2000;54:125–132. 11. Berry C. Your Voice, and How to Use it Successfully. London: Harrap; 1993. 12. Rodenburg P. The Right to Speak: Working with the Voice. London: Methuen Drama; 1992. 13. Duffy J. Motor Speech Disorders. 2nd ed. Missouri: Elsevier Mosby; 2005. 14. Morgan, P, McCabe, P, Madill, C. Do acting students have the same voice qualities as non-acting students? Poster presented to the International Association of Logopaedics and Phoniatrics (IALP) Congress, Brisbane, Australia; 2004. 15. Cusiter J. Dysphonia related to inhaled corticosteroid treatment in asthma: Effects of dosage reduction. Unpublished Honours thesis, University of Sydney, Sydney; 2004.
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16. Brown W, Rothman H, Sapienza C. Perceptual and acoustic study of professionally trained versus untrained voices. J Voice. 2000;12:301–309. 17. Fairbanks G. Voice and Articulation Drill Book. New York: Harper & Row; 1960. 18. Goodglass H, Kaplan E, Barresi B. Boston Diagnostic Aphasia Examination. 3rd ed. Philadelphia, PA: Lippincott, Williams & Wilkins; 2001. 19. Goozee J, Murdoch B, Theodoros D, Thompson E. The effects of age and gender on laryngeal aerodynamics. Int J Lang Commun Disord. 1998;33:221–238. 20. Mathieson L. Greene and Mathieson’s: The voice and its disorders. 6th ed. London: Whurr; 2001. 21. Perneger T. What is wrong with Bonferroni adjustments. Br Med J. 1998;136:1236–1238. 22. Raphael B, Scherer R. Voice modifications of stage actors: acoustic analyses. J Voice. 1987;1:83–87. 23. Cooper M. Spectrographic analyses of fundamental frequency and hoarseness before and after vocal rehabilitation. J Speech Hear Disord. 1974;39:286–297. 24. Koufman J, Blalock PD. Vocal fatigue and dysphonia in the professional voice user: Bogart-Bacall syndrome. Laryngoscope. 1998;98:493–499. 25. Colton R, Casper J, Hirano M. Understanding Voice Problems: A Physiological Perspective for Diagnosis and Treatment. 2nd ed. Baltimore: Lippincott Williams & Wilkins; 1996. 26. Timmermans B. Poor voice quality in future elite vocal performers and professional voice users. J Voice. 2002; 16:372–382. 27. Emerich K, Titze I, Svec J, Popolo P, Logan G. Vocal range and intensity in actors: a studio versus stage comparison. J Voice. 2005;19:78–83. 28. Reid, KLP. An investigation of theatre voice training (based on the Linklater method). Unpublished PhD thesis, University of Sydney; 2003.
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PETA WALZAK ET AL APPENDIX A
Voice Qualities of Actors Voice Questionnaire Based on Sataloff, 1998 Subject Number __________________
Date ______/______/_______
Age _________
Height ___________________
Sex _________
Weight ___________________
Occupation _____________________________________ (1) How much do you use your voice at work every day: (please circle) 1–2 hours
2–4 hours
4–6 hours
6–8 hours
more than 8 hours
(2) Do you use a loud voice at work? Yes/No (3) Do you use a loud voice at home? Yes/No (4) Have you ever had training for your speaking or singing voice? Yes/No If “yes” please provide details (for how long, where, what kind of training): _________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ (5) How much sleep do you get (on average) every night: less than 4 hours
4–6 hours
6–8 hours
8–10 hours
more than 10 hours
(6) Do you exercise regularly? Yes/No If “yes” please give details:________________________________________________________ ______________________________________________________________________________ (7) How much alcohol do you drink? ______________________________________________________________________________ ______________________________________________________________________________
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(8) How many cups of coffee, tea, cola, or other caffeine-containing drinks do you drink per day? ______________________________________________________________________________ ______________________________________________________________________________ (9) Have you ever smoked? Yes/No If “yes” please provide details (for how long, how many, how long since you quit):___________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ (10) Do you live or work in a smoky environment? Yes/No If “yes” please give details:________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ (11) List any other recreational drugs you use: ______________________________________________________________________________ ______________________________________________________________________________ (12) Have you noticed any of the following in the last 6 months? (please tick all that apply) Voice worse in the morning Voice worse later in the day, after it has been used Frequently clear your throat Frequently experience sore throat / sensation in the throat Jaw joint problems Bitter or acid taste; bad breath in the morning Frequent “heartburn” or hiatus hernia Frequent yelling or loud talking Frequent whispering Chronic fatigue/insomnia Work in dry or dusty conditions Eat late at night Ever used antacids Frequent bad breath Lived or worked around smoke or fumes If “yes” please give details: _________________________________________________ ______________________________________________________________________________ Frequently felt tired Work shift work Frequently thirsty/dehydrated Traveled recently: When _______________________________________________________ Where ________________________________________________________________________ (13) Have you noticed any changes in your voice in the last 6 months? Yes/No If “yes” please give details: _______________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ Journal of Voice, Vol. 22, No. 3, 2008
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(14) If “yes”, do you know what caused these changes? Yes/No If “yes” please give details:________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ (15) Did it come on slowly/suddenly? (circle one) (16) Is it getting worse/better/same (circle one) (17) Have you used your voice excessively (yelling/screaming) anytime over the last 6 months? Yes/No If “yes” please give details:_______________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ (18) Has any one commented on your voice? Yes/No If “yes” please give details:_______________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ (19) Have you experienced any of the following in the last 6 months? (Tick all that apply) Hoarseness (coarse or scratchy voice quality) Vocal fatigue (voice tires or changes quality after speaking for a short period of time) Difficulty speaking softly or loudly (circle which one applies) Loss of vocal range (high/low) Breathiness Tickling or choking sensation when speaking Pain in the throat when speaking Loss of voice Any other vocal difficulties/symptoms: _____________________________________________ ______________________________________________________________________________ ______________________________________________________________________________
(20) Have you noticed any of the following in the last 6 months? (Tick all that apply) Change in weight: gained/lost _____ kg in _____ weeks/months Excessive sweating Change in skin or hair Palpitation (fluttering) of the heart Numbness of the face or hands/feet Double vision / Blurred vision Confusion, dizziness,or loss of consciousness Difficulty with speech Difficulty with swallowing Journal of Voice, Vol. 22, No. 3, 2008
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Seizure (epileptic fit) Pain/stiffness in the neck or shoulder Shaking or tremors Memory change Personality change Hearing loss Ear pain Facial pain Lump in neck, face, or head Ear noises Nasal obstruction/deformity Nose bleeds
(21) Female subjects: Are you pregnant? Yes/No Are your menstrual periods regular? Yes/No Have you undergone a hysterectomy? Yes/No Were your ovaries removed? Yes/No Have you gone through menopause? Yes/No At what age did you reach puberty? __________ Are you currently menstruating? Yes/No Are you currently ovulating? Yes/No/Don’t know
(22) Male subjects: At what age did you reach puberty? _________ At what age did your voice break? __________
(23) All subjects: Have you suffered from any of the following in the last 6 months? (Tick all that apply) If “yes” please provide details: Cough (lasting more than 1 month) _______________________________________________ Bronchitis __________________________________________________________________ Sinusitis ____________________________________________________________________ Colds and/or flu ______________________________________________________________ Journal of Voice, Vol. 22, No. 3, 2008
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Allergies ___________________________________________________________________ Asthma ____________________________________________________________________ (24) Are you taking any medication for the above? Yes/No If “yes” please give details: _______________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ (25) Have you ever injured your head or neck? Yes/No If “yes” please give details:________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ (26) Have you been in any serious accidents? Yes/No If “yes” please give details:________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ (27) Have you experienced any heightened emotional situations in the last 6 months (eg, death of a loved one, stress at work, disagreement with family)? Yes/No If “yes” please give details:________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ (28) Have you experienced any heightened emotional situations in the last 24 hours? Yes/No If “yes” please give only basic details: _______________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ (29) Please tick any that apply to you TODAY: I feel tired/fatigued I am thirsty/dehydrated I feel anxious I feel depressed I feel angry I feel upset
Thank you for your time in filling out this questionnaire.
Journal of Voice, Vol. 22, No. 3, 2008
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APPENDIX B Voice Screening: The Interview Introduction: explain who you are, what’s going to happen, the format of today’s session Name, address, telephone number, age, DOB Any major voice symptoms, problems? (Describe; indicate severity); Sources? (eg, “Ok, maybe we could start off with just a few questions about your voice. Have you ever lost your voice? I mean, not just the odd bout of laryngitis. How long ago was that? Did it clear up all right? …Tell me what happens if you overdo the voice stuff? Do you notice anything? Does your voice ever give out on you? What happens when your voice is tired?) Eg, hoarse, husky or rough voice, reduced vocal range, pain in throat area
Explore potential risk factors as they arise (see below) Any problems with speech? (eg, articulation) Describe previous voice/speech training Health Upper respiratory tract symptoms—include description of severity of: - asthma; cough - excessive mucus production; chest/nasal airways (eg, postnasal drip) - sinusitis - bronchitis - allergies Ear infections, otitis media
Describe treatment sought (doctors, etc) and outcome List any medications used. Ask if taking any regular prescribed medication.
Describe current voice quality (eg, Is today good or bad?) Rough, clear, low pitched, high pitched, slightly hypernasal, phonation breaks, hyponasal, monotonous, breathy, strong, loud, rich, resonant, soft, etc. Make an observation about their voice (eg, “I notice that your voice as a slight rough edge to it. Is that how it is normally? It also seems quite low pitched. Has anyone commented to you about that?”)
Potential risk factors Loud talking, shouting, screaming Excessive voice use Tension Excessive singing Fast speech Throat clearing History of respiratory tract problems Hard glottal attack Speaking in loud background noise (eg, clubs) Smoking Excessive use of stimulants/diuretics Sore throat
Always remember to ask about - drinking - smoking - hearing Journal of Voice, Vol. 22, No. 3, 2008