A comparative acoustic study of hanoi vietnamese and general american english monophthongs

Vietnam national university, Hanoi University of languages and international studies Faculty of Post graduate studies DOÃN MINH MÃO A comparative acoustic study of Hanoi Vietnamese and general American English monophthongs Phân tích âm học so sánh hệ thống nguyên âm đơn Tiếng Việt Hà Nội tiếng Anh Mỹ Phổ th«ng A thesis submitted to the Faculty of Post Graduate Studies, University of Languages and International Studies, VNU, Hanoi in partial fulfillment of the requirements for the degree of Master of Arts in English Linguistics Code: 60.22.15 HA NOI – 2012 i Vietnam national university, Hanoi University of languages and international studies Faculty of Post graduate studies DOÃN MINH MÃO A comparative acoustic study of Hanoi Vietnamese and general American English monophthongs Phân tích âm học so sánh hệ thống nguyên âm đơn Tiếng Việt Hà Nội tiếng Anh Mü Phỉ th«ng A thesis submitted to the Faculty of Post Graduate Studies, University of Languages and International Studies, VNU, Hanoi in partial fulfillment of the requirements for the degree of Master of Arts in English Linguistics Code: 60.22.15 Supervisor: Pham Xuan Tho, M.A HA NOI – 2012 ii LIST OF TABLES Table Title The first and second formant frequencies of all the subjects for Page 34 each vowel The values of the first and the second token of each sound 47 produced by each speaker The average values of F1 and F2 for each vowel as spoken by 53 ten speakers vi LIST OF FIGURES Figure Title Page The spectrogram of the author’s pronunciation of [i] in hi 18 The effect of [ɲ] on [i] in inh and nhi, as produced by the researcher The effect of [ɲ]on [a] in nha 34 The difference between the vowel in e and anh, produced by a subject The difference between the vowel in e and anh, produced by another subject The similarities between the vowel in anh and ay, produced by a subject The similarities between the vowel in anh and ay, produced by another subject Spectrograms of [ɤ]and [ɤ̆n ] Spectrograms of [ɤn], on the left, and [ɤ̆ n], on the right The similarities between the vowel in a [a] and ay [ăi], produced by a subject The spectrogram of [a] is on the left, and of [ăi] is on the right The duration of [a] and [ă] in ai, on the left, and ay, on the right The correlation between the two measurements of each F1 and F2 by the first subjects The monophthongs of ten speakers of Vietnamese in Hanoi dialect The formant chart showing the average values of F1 and F2 for each monophthong as spoken by ten speakers A formant chart showing the formant frequency F1 and F2 for eight English monophthongs The scales are marked in Hz, arranged at Bark scale intervals The formant chart of Vietnamese monophthongs produced by female speakers 38 The formant chart of General American English monophthongs produced by female speakers 58 10 11 12 13 14 15 16 17 36 38 39 39 41 42 44 45 50 53 54 56 57 vii TABLE OF CONTENTS STATEMENT OF AUTHORSHIP i ABSTRACT iv ACKNOWLEDGEMENT v LIST OF TABLES vi LIST OF FIGURES vii TABLE OF CONTENTS viii Chapter 1: INTRODUCTION 1 Rationales Scope of the research and the research questions Chapter 2: THE REVIEW OF LITERATURE 2.1 The articulatory description of Hanoi Vietnamese monophthongs 2.2 The acoustic description attempts 10 2.3 Characterizing vowel qualities with the acoustic properties 16 2.4 General American English 24 2.4.1 The traditional description 24 2.4.2 The acoustics of GA 27 Chapter RESEARCH METHODOLOGY .30 3.1 The subjects 30 3.2 The stimuli 30 3.3 The recording process 31 3.4 The analysis process 32 Chapter 4: FINDINGS AND DISCUSSION 34 4.1 The acoustics of Hanoi Vietnamese monophthongs 34 4.1.1 [ɛ̆] and [ɛ] 35 4.1.2 [ɤ] and [ɤ̆] 40 4.1.3 [a] and [ă] 43 viii 4.1.4 Regression analysis 48 4.1.5 Charting the formants of Hanoi Vietnamese monophthongs 51 4.2 The monophthongs of Hanoi Vietnamese and General American English in comparison 58 Chapter CONCLUSION 62 5.1 The main findings on the acoustics of Hanoi Vietnamese monophthongs 62 5.2 The monophthongs of Hanoi Vietnamese and General American English in comparison 63 5.3 The limitations of the study and suggestions for further research 64 REFERENCES .66 Appendix 1: Phiếu chấp thuận tham gia vào nghiên cứu 68 Appendix 2: The stimuli 69 ix Chapter 1: INTRODUCTION Rationales The ultimate aim of this research is to achieve a cross language comparison between the acoustic properties of Hanoi Vietnamese monophthongs and General American English monophthongs The findings of the accomplished study are significant, from both the linguistic and pedagogical perspectives Ladefoged states firmly that, “The best way of describing vowels is not in terms of the articulations involved, but in terms of their acoustic properties.” (2003, p.104) A considerable amount of space of this thesis is devoted to the researcher’s analysis of the monophthongs, or pure vowels (Wells, 1962, p.1) of Vietnamese, Hanoi dialect Aside from a few studies conducted overseas, which have important limitations to be addressed, which are discussed in details in the Review of Literature of this thesis, there has been no attempt to study the vowel acoustics of the recognized standard Vietnamese so far The literature on Vietnamese vowel acoustics has been mainly concerned with the description of the sounds from the views of articulatory phonetics The investigations conducted by Nguyễn (1998), and Đoàn (2000) are typical examples These studies examined the behaviors of the vocal organs involved in the articulatory process when a particular sound is being produced This method, while having the advantage of being straightforward, has put forwards ideas which remain an approximation to the truth Ladefoged and Johnson (2011, p.197) comment, Traditional articulatory descriptions are often not in accord with the actual articulatory facts For well a hundred years, phoneticians have been describing vowels in terms such as high versus low and front versus back To some extent, they have been using these terms as labels to specify acoustic dimensions rather than as descriptions of actual tongue positions Phoneticians are thinking in terms of acoustic fact, and using physiological fantasy to express the idea Acoustics offers sufficient tools for explaining the vowel qualities The production of a speech sound involves firstly the vibration of the vocal cords, which produces sound waves It involves secondly the performance of the vocal tract, which can be changed into various shapes, as a filter, under the acoustic impedance Vowel sounds are characterized acoustically by formants, which are frequency regions of high energy concentration corresponding to the pass bands of the throat and mouth cavities (Wells, 1962, p.1).Therefore, instead of only studying a particular sound from the outside, rather subjectively, by observing with eyes, trying to set up a collection of its articulatory features, there should be a rigorous description method where every dimension of a sound as its nature is measured and displayed objectively on the screen of an electronic device The analysis, carrying out appropriately, would result in an acoustic vowel chart, representing accurately the linguistic aspects of Hanoi Vietnamese monophthongs, which serves as a valuable source of reference for cross language comparison The pronunciation of General American English and of Hanoi Vietnamese are acknowledged as the reference accents of English and Vietnamese respectively As a result, from the pedagogical aspect, the findings of the research are of highly practical values in teaching the pronunciation of one language to learners of the other language Scope of the research and the research questions The study first examined the quality of the pure vowels in Hanoi Vietnamese The frequencies of each of the first two formants of each monophthong (F1, F2) were investigated on the acoustic spectrographs, generated from the speech analyzer program PRAAT The results obtained from the analysis were then compared with the results of a recent research in the monophthongs of General American English, conducted by Clark, M J, Hillenbrand, J, et al (1995) The research is aimed at answering two questions: 1) What are the acoustic properties characterizing Hanoi Vietnamese monophthongs? 2) What are the common and distinctive features between the relative positions of the monophthongs in Vietnamese and General American English on the formant charts? Figure 14: The formant chart showing the average values of F1 and F2 for each monophthong as spoken by ten speakers In the chart above, the axes and the tick marks have been simplified and arranged in accordance with Hillenbrand et al (1995) for the sake of the vowel quality comparison in the later section of this thesis The vowel [i] occupies a position on the chart which is highest and farthest to the left, featuring the most front and close vowel of the inventory The vowel [e] is slightly lower and further back, indicating the close-mid front qualities While [ɛ] is below [e] and is a short distance further to the left, featuring a relatively open-mid 55 front vowel, it must be emphasized that these two vowels have considerable degree of similarity At this point, a drawback of the plotting program must also be taken into account The marks on F2 axe are equally spaced, 200 Hz apart, which has been shown not to reflect how the human sense of hearing really perceives the sounds While with the frequency between 300 and 1000 Hz, the perceived pitch of a note increases linearly, so that the difference in pitch of a note with frequencies of 300 Hz and 400 Hz is much the same as the difference between notes with frequencies of 500 Hz and 600 Hz However, between 1000 and 10000 Hz, the pitch interval between two notes depends on the ratio of the frequencies, rather than the absolute value of the difference between the note with the higher frequency and the note with lower frequency For example, there is an equal interval of pitch between notes from 1200 Hz to 2400 Hz and notes from 4000 Hz to 8000 Hz, as the ratios between the higher and the lower note in these two pairs both equal ½ The figure below illustrates how Ladefoged (2011, p.187) adjusts the tick mark spacing on F2 axe to reflect what would better reflect the human perception of audio frequency As it can be seen, for frequencies above 1000 Hz, the space between tick marks is increasingly closer relatively with the increase of the frequencies 56 Figure 15: A formant chart showing the formant frequency F1 and F2 for eight English monophthongs The scales are marked in Hz, arranged at Bark scale intervals Taking this into account, [a] and [ă], despite having F2 at the middle of the axe segment, would in fact be more front than those at the central of the chart They are also the most open vowels in the inventory, with [ă] being very slightly farther down on F1 axe The difference in F2, indicating the front and back quality differences, is insignificant In the central area of the chart, there are three vowels, [ɯ], [ɤ], and [ɤ̆] While [ɯ] is typically close, with very low F1, the others feature mid-open vowels, and are a relatively short distance further to the right The differences between [ɤ] and [ɤ̆] in terms of F1 and F2, or 57 the front, back, close, open qualities is of little importance in contrasting one from the other, although the later vowel has higher F1 It is the duration that must be taken into consideration here, as Đoàn (ibid., p.197) always insists As compared to the previous group, [ɔ] is a more open and more back vowel, but not as open as [a], and is not far enough to the right of the chart so as to be considered a typically back vowel The two remaining vowels are [u] and [o] The former is as close as [ɯ], and is the most back vowel, with [o] is a little more front and more open 4.2 The monophthongs of Hanoi Vietnamese and General American English in comparison 58 Figure 16: The formant chart of Vietnamese monophthongs produced by female speakers Figure 17: The formant chart of General American English monophthongs produced by female speakers Before the comparison can be drawn, it must be highlighted that due to the anatomical differences between Vietnamese females and American females, a comparison and contrast of the absolute value of the formant frequencies will not reflect the actual differences and similarities in vowel qualities Rather, the researcher will make an attempt to compare the relative positions of the vowels on the formant charts It is obvious from the charts that both [i] of Vietnamese and of General American have noticeable similarities They are the most 59 close and front vowel in both systems Despite this, the Vietnamese vowel appears to be higher than the American counterpart In the front positions, Vietnamese has two other vowels, [e] and [ɛ], while General American has three, [i], [ɛ], and [æ] In spite of the very different represented phonetic symbols, [e] in Vietnamese, like in hết and [i] of American, as in hit, show considerable quality equivalence The situation is much the same for the other pair in consideration: [ɛ] of Vietnamese and [æ] of American English They are both a short distance lower on the charts The remaining American vowel [ɛ] is deviant from the group It is farther to the central, and also more open The central area of the chart also deserves careful attention Asides from appearing to be closer, the Vietnamese [ɯ] and the American counterpart [ɝ] show some important similarity It must be noted, though, that the additional r quality may make the sounds sound less similar [ʌ], [ɤ]and [ɤ̆], on the other hand, show strikingly close quality The vowel [ɑ] of American English and [a] of Vietnamese are both very open, but the latter is considerably farther to the front area In the back area of the chart, both Vietnamese and American English have a vowel represented as [u] and another vowel, as [ɔ] They 60 also occupy much the same positions on the chart The qualities of each vowel in these pairs are, therefore, expected to be very alike The remaining vowel, [o] in Vietnamese, and [ʊ] in American English, are quite different The first vowel is much lower, and is slightly more back 61 Chapter CONCLUSION 5.1 The main findings on the acoustics of Hanoi Vietnamese monophthongs In this study, the researcher has made an attempt to give a description of the monophthongs in Hanoi Vietnamese, based on the acoustic measurements of the formant frequencies Despite the shortcomings of the research, it has discovered important results The measurements and comparison of F1 and F2 among the monophthongs have pointed out that there is not a vowel which has been traditionally described and represented by /ɛ̆/ in some accounts in literature The average formant frequencies values have demonstrated that the qualities of this vowel is much the same as those of /ă/ and /a/ It has also been highlighted that the latter vowel is contrasted from the previous essentially by the vowel duration This strongly supports the claims made by Đoàn (2000) that duration is the distinguishing features of these vowels As a result, it is suggested that /ɛ̆/ and /ă/ are equated, and the later phonetic symbol will be arguably able to represent both The situation is subtly different for /ɤ̆/ and /ɤ/ The former vowel has slightly higher F1 and F2 than the later vowel, featuring its quality as being more front and more open This has somewhat gone against previous studies which maintain that these vowels are of the same quality, but different in terms of the duration Despite this fact, it 62 must be acknowledged that they are fundamentally similar, and that the duration contrast clearly plays an important role in distinguishing one from the other The formant chart (vowel chart) has also added that they are vowels being typically central Another pair of vowels, /a/ and /ă/, have also been shown to have radical similarity in qualities While the former is marginally more front and more close, it must be accepted that the degree of similarity is significant It should also be noted again that it is the duration difference that distinguishes them from each other The last vowel whose description has generated heated debate among phoneticians is /ɯ/ The measurement of F1 and F2, and the position it occupies on the formant chart suggests that this is a close central vowel 5.2 The monophthongs of Hanoi Vietnamese and General American English in comparison This research has also been set out to provide a comparison between the relative positions of the monophthongs in Vietnamese and General American English on the formant charts The result is of keen interest and is highly suggestive in language education It is interesting that many monophthongs in both languages share their position with a sound of the other language on the format chart , despite the different phonetic symbols which represent them The Vietnamese /e/ is surprisingly similar to the American /i/, although 63 the former appears to be more open In the same way, the vowel /æ/ in American English, which has been shown to be substantially different from the counterpart of RP, shares its important qualities with /ɛ/ of Vietnamese /ʌ/, /u/, and /ɔ/ are three other vowels which have strikingly similar sounds in Vietnamese, being /ɤ/, /u/, and /ɔ/ respectively In this group, that /ʌ/ and /ɤ/ share their qualities has been mentioned in literature 5.3 The limitations of the study and suggestions for further research Despite its achievements, there are important limitations in the current study, which have been pointed out to some extent aforementioned The spectrograms have failed to present the formant frequencies of the vowel [ɔ̆] in measurable contours This vowel, as described in the chapter of research methods, is realized in the chosen word óc The failure is due to the limited distribution of the vowel, as being accounted for in literature The consonant following [ɔ̆] has shortened it significantly, resulting in the very short formant contours Added to this, this consonant ([k]), also has great influence on the vowel’s formants, changing its value considerably, aggravating the situation 64 As it has been pointed out, it is possible that the vowel in anh is not purely [ă], but there is possibly a glide to a second vowel, characterizing an [i] before the influence of the following consonant can take effect However, as this consonant, as analyzed, has its formant frequency values almost equal to those of [i], the attempt to prove that [i] exists has been of little success Ladefoged (2011, p.212) has pointed out that although the absolute values of the formant frequencies between men and women, between children and adults are generally different, due to the anatomical differences, the relative positions of the vowel on the charts, indicating how the vowels are articulated, are similar Nevertheless, if this thesis had investigated the pure vowels produced by two other groups, men and children, the research results would have been more insightful Finally, the study has not described all the dimensions of the Vietnamese monophthong qualities Discussion on the findings of the research, as well as the review of literature has suggested that there are pure vowels in Vietnamese whose qualities cannot be described based solely on the qualities of being close or open, front or back, or on the frequencies of the first two formants It is the duration that plays a crucial part This study has not investigated this dimension 65 REFERENCES Billerey, J (2001) JPlotFormants v1.4: Formant-plotting software Retrieved from http://www.linguistics.ucla.edu/people/grads/billerey/PlotFrog.htm Clark, M J, Hillenbrand, J, et al (1995) Acoustic characteristics of American English vowels Journal of Acoustical Society of America 97(5) Đoàn, T T (2000) Ngữ âm Tiếng Việt Hà Nội: Nhà xuất Đại học Quốc gia Hà Nội Gimson, A.C (2008) Pronunciation of English Oxford: Oxford University Press Gomez, E.T (2012) British and American English Pronunciation Differences Retrieved from http://www.webpgomez.com/index.php?option=com_content&view= article&id=332&Itemid=51 Johnson, K (2005) Speaker normalization in speech perception Retrieved from http://www.phonetik.unimuenchen.de/~reichelu/kurse/perz_fort/liter atur/JohnsonHSP2005.pdf Johnson, K., Ladefoged, P & Lindau, M (1993) Individual differences in vowel production Journal of Acoustical Society of America 94, 701-714 Ladefodged, P & Johnson, K (2011) A Course in Phonetics Boston: Wadsworth Ladefoged, P (2003) Phonetic Data Analysis: An Introduction to Fieldwork and Instrumental Techniques Oxford: Blackwell Publishing Ladefoged, P (2005) Vowels and Consonants Oxford: Blackwell Publishing 66 Ladefoged, P (1996) Elements of Acoustic Phonetics Chicago: University of Chicago Press Lindau, M (1978) Vowel features Language, 54(3), 541 -563 Matt, W et al (2009) Vietnamese Vowel, the Central Focus Retrieved from http://www.casl.umd.edu/sites/default/files/WinnTwistBlodgett_Viet nameseVowelsSec22009.pdf Mai, N C, Vu, D.N & Hoang, T.P (2008) Cơ sở ngôn ngữ học Tiếng Việt Hà Nội: Nhà xuất Giao dục Việt Nam Nguyen, B & Srihari, R (2004) A preliminary quantitative study on the characteristics of Vietnamese vowels and English vowels Retrieved from http://www.cs.jhu.edu/~nguyen/data/phonetics_prjrpt.pdf Pham, A (2003) Vietnamese tone: A new analysis Outstanding Dissertations in Linguistics New York: Routledge Shure Americas (2012) PG27USB Spec Sheet Achieved from http://www.shure.com/specificationsheets/us_pro_pg27usb_specsheet.pdf Thompson, L.C (1965) A Vietnamese Reference Grammar Hawaii: University of Hawaii Press Thompson, L.C (1987) A Vietnamese Reference Grammar Hawaii: University of Hawaii Press Wells, J.C (1982) Accents of English Cambridge: Cambridge University Press Wells, J.C (1962) A study of the formants of the pure vowels of British English (MA Thesis) Retrieved from http://www.phon.ucl.ac.uk/home/wells/formants/index.htm Weenink, D & Boersma, P (2012) Praat: doing phonetics by computer Retrieved from http://www.fon.hum.uva.nl/praat/ 67 Appendix 1: The ethic form Đại học Ngoại ngữ - Đại học Quốc gia Hà Nội Khoa Sau Đại học Phiếu chấp thuận tham gia vào nghiên cứu Tên đề tài: Phân tích âm học so sánh nguyên âm đơn tiếng Việt Hà Nội tiếng Anh Mỹ Phổ thông Tôi đọc tờ phiếu thông tin tác giả nghiên cứu giải thích thơng tin liên quan đến đề tài Tác giả giải thích cách rõ ràng mục đích đề tài, yêu cầu với người tham gia nghiên cứu, đồng thời trả lời thỏa mãn câu hỏi từ phía tơi Tơi đồng ý với kế hoạch đưa Phiếu thơng tin liên quan đến q trình tham gia nghiên cứu Tơi hiểu việc tham gia vào đề tài hoàn toàn tự nguyện tơi có quyền dừng tham gia q trình nghiên cứu vào thời điểm muốn Tôi nhận Phiếu chập thuận tờ phiếu thông tin kèm Tên: Chữ ký: Ngày tháng: 68 Appendix 2: The stimuli Phần Hướng dẫn: Đọc đoạn giới thiệu truyện cổ tích Tấm Cám Giọng đọc bạn ghi âm.Trước đọc, bạn có 10 giây để chuẩn bị “Tấm Cám câu chuyện cổ tích Việt Nam thuộc thể loại truyện cổ tích thần kì, phản ánh mâu thuẫn gia đình, đấu tranh thiện ác, ước mơ thiện thắng ác người Việt Nam.” (Nguồn: Wikipedia) Phần Hướng dẫn: Đọc từ/chữ xuất hai lần Câu trả lời bạn ghi âm Trước đọc, bạn có 10 giây để chuẩn bị i ê e anh u o óc 10 11 ân 12 a 13 ay 69 ...Vietnam national university, Hanoi University of languages and international studies Faculty of Post graduate studies DOÃN MINH MÃO A comparative acoustic study of Hanoi Vietnamese and general American. .. monophthongs and General American English monophthongs; this section is devoted for an examination of the concept of General American English (GA) and its monophthongs in literature Generally, phoneticians... English monophthongs The scales are marked in Hz, arranged at Bark scale intervals The formant chart of Vietnamese monophthongs produced by female speakers 38 The formant chart of General American English