• Phonetics and Speech Sciences
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• v.3 no.1
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• pp.23-34
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• 2011

Many Korean children have difficulty learning English vowels. The gestures inside the oral and pharyngeal cavities are hard to control when they cannot see the gestures and the target vowel system is quite different from that of Korean. This study attempts to collect children's acoustic data of twelve English vowels published by Hillenbrand et al. (1995) online and to examine the acoustic features of English vowels for phoneticians and English teachers. The author used Praat to obtain the data systematically at six equidistant timepoints over the vowel segment avoiding any obvious errors. Results show inherent acoustic properties for vowels from the children's distribution of vowel duration, f0 and intensity values. Second, children's gestures for each vowel coincide with the regression analysis of all formant values at different timepoints regardless of the vocal fold and tract difference. Third, locus points appear higher than those of American males and females. Their gestures along the timepoints display almost similar patterns. From the results the author concludes that vowel formant trajectories provide useful and important information on dynamic articulatory gestures, which may be applicable to Korean children's education and correction of English vowels. Further studies on the developmental study of vowel formants and pitch values are desirable.

• Phonetics and Speech Sciences
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• v.11 no.4
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• pp.97-108
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• 2019

An automated Praat script was implemented to measure optimal formant frequencies for adults. Optimal formant analysis could be interpreted to show that the deviation of formant frequency that resulted from the two variously combined setting parameters (maximum formant and number of formants) was minimal. To increase the reliability of formant analysis, LPC order should be set differently, based on the gender or vowel type. Praat recommends 5,000 Hz and 5,500 Hz as maximum formant settings and, at the same time, recommends 5 as the number of formants for males and females. However, verification is needed to determine whether these recommended settings are valid for Korean vowels. Statistical analysis showed that formant frequencies significantly varied across the adapted scripts, especially with respect to the data on females. Formant plots and statistical results showed that linear_script and qtone_script are much more reliable in formant measurements. Among four kinds of scripts, the linear and qtone_scripts proved to be more stable and reliable. While the linear_script was designed to have a linearly increased formant step in for-loop, the increment of formant step in the qtone_script was arranged by quarter tone scale (base frequency×common ratio ($\sqrt[24]{2}$)). When looking at the tendency of the formant setting drawn by the two referred algorithms in the context of front vowel [i, e], the maximum formant was set higher; and the number of formants set at a lower value than recommended by Praat. The back vowel [o, u], on the contrary, has a lower maximum formant and a higher number of formants than the standard setting.

• Speech Sciences
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• v.15 no.3
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• pp.39-51
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• 2008

Formant measurements are one of the most important factors to objectively test cross-linguistic differences among vowels produced by speakers of any given languages. However, many speech analysis softwares present erroneous estimates and some researchers use them without any verification procedures. The purposes of this paper are to examine formant measurements of complex waves which were synthesized from the average formant values of five Korean vowels using three default methods in Praat and to verify the measured values of the five vowels produced by 20 students using one of the methods. Variances along the time axis are discussed after determining absolute difference sum from the 1/3 vowel duration point. Results show that there were smaller measurement errors by the burg method. Also, greater errors were observed in the sl or lpc methods mostly caused by the inappropriate formant settings. Formant measurement deviations were greater in those vowels produced by the female students than those of the male students, which were mostly attributed to the settings for the vowels /o, u/. Formant settings can best be corrected by changing the number of formants to the number of visible dark bands on the spectrogram. Those results suggest that researchers should check the validity of the estimates from the speech analysis software. Further studies are recommended on the perception test of the original sound with the synthesized sound by the estimated formant values.

• Speech Sciences
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• v.11 no.2
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• pp.165-177
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• 2004

Western singers voice have been studied in music science since the early 20th century. However, Korean traditional singers voice have not yet been studied scientifically. This study is to find the physiological and acoustic characteristics of Pansori singers voices. Western singers participated for comparative purposes. Ten western singers and ten Pansori singers participated in this study. The subjects spoke and sung seven simple vowels /a, e, i, o, u, c, w/. An analysis of Glottal image was done by Scope View and acoustic characteristics of speech and singing voice were analyzed by CSL. The results are as follows: (1) Glottal gestures of Pansori singers showed asymmetric vocal folds. (2) Singing vowel formants of Pansori singers showed breathiness based on Spectrogram. (3) Music formant of western singers appeared in around 3kHz area, however, Pansori singers formant appeared in low frequency area. Modulation of vibrato showed 6 frequency per sec in case of western singers. Pansori singers showed no deep modulation of vibrato on spectrogram.

• Journal of Korean language education
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• v.29 no.2
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• pp.155-180
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• 2018

The purpose of this study is to acoustically analyze eight Korean monophthongs produced by 29 Taiwanese learners of Korean and 20 native speakers of Korean, and to compare their pronunciations in experimental phonetics. Using the first formants(F1) and the second formants(F2) of Korean monophthongs, we can estimate the tongue positions of vowels produced by participants. In order to compare them directly, we had to normalize participants' F1 and F2. The result shows that almost all vowels of the Taiwanese learners are significantly different from those of Korean native speakers in their F1 and F2 values without the /ㅏ/ vowel. In particular, when pronouncing Korean monophthongs, the Korean learners of Taiwan had a narrow area of the place of articulation compared to the Korean native speakers except for back vowels. Finally, it shows that the Korean learners in Taiwan had a narrower range of articulation and articulated the vowels towards the back a little comparing to the Korean native speakers.

• Speech Sciences
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• v.1
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• pp.201-211
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• 1997

Acoustically a naturally-spoken vowel is composed of five formants. However, the acoustic quality of a vowel is known to be mostly determined by $F_1\;and\;F_2$. The main purpose of this study was to examine how synthesized vowels with $F_1\;and\;F_2$ are perceived by Korean native speakers. In addion, we are interested in finding whether the synthesized vowels are perceived differently by standard Korean speakers and Kyungnam regional dialect speakers. In the experiment 9 Seoul standard Korean speakers and 9 Kyungnam dialect speakers heard 536 vowels synthesized in vowel space with $F_1\;by\;F_2$ and categorized them into one of 10 Korean vowels. The resultant vowel map showed that each Korean vowel occupies an unique area in the two-dimensional vowel space of $F_1\;by\;F_2$, and confirmed that $F_1\;and\;F_2$ play important roles in the perception of vowels. The results also showed that the Seoul speakers and the Kyungnam speakers perceive the synthesized vowels differently. For example, /e/ versus /$\varepsilon$/ contrast, /y/, and /$\phi$/ are perceived differently by the Seoul speakers, whereas they were perceptually confused by the Kyungnam speakers. These results might be due to the different vowel systems of the standard Korean and the Kyungnam regional dialect. While the latter uses a six-vowel system which has no /e/ vs /$/ contrast, /v/ vs /i/ contrast, /y/, and /$\phi$/, the former recognizes these as different vowels. This result suggests that the vowel system of differing dialect restricts the perception of the Korean vowels. Unexpectedly /i/ does not occupy any area in the vowel apace. This result suggests that /i/ cannot be synthesized without $F_3$.

• Phonetics and Speech Sciences
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• v.7 no.2
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• pp.157-162
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• 2015

This study reports on the effective way of displaying dynamic formant information on F1-F2 space. Conventional ways of F1-F2 space (different name of vowel triangle or vowel rectangle) have been used for investigating vowel characteristics of a speaker or a language based on statistics of the F1 and F2 values, which were computed by spectral envelope search method. Those methods were dealing mainly with the static information of the formants, not the changes of the formant values (i.e. dynamic information). So a better way of investigating dynamic informations from the formant values of speech signal is suggested so that more convenient and detailed investigation of the dynamic changes can be achieved on F1-F2 space. Suggested method used visualization of static and dynamic information in overlapped way to be able to observe the change of the formant information easily. Finally some examples of the implemented display on some cases of the continuous vowels are shown to prove the usefulness of suggested method.

• Phonetics and Speech Sciences
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• v.3 no.1
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• pp.45-50
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• 2011

Formant structure of speech associated with five different emotions (anger, fear, happiness, neutral, sadness) was analysed. Acoustic separability of vowels (or emotions) associated with a specific emotion (or vowel) was estimated using F-ratio. According to the results, neutral showed the highest separability of vowels followed by anger, happiness, fear, and sadness in descending order. Vowel /A/ showed the highest separability of emotions followed by /U/, /O/, /I/ and /E/ in descending order. The acoustic results were interpreted and explained in the context of previous articulatory and perceptual studies. Suggestions for the performance improvement of an automatic emotion recognition system and automatic speech recognition system were made.

• Journal of The Korean Society of Integrative Medicine
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• v.7 no.4
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• pp.89-104
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• 2019

Purpose : The purpose of this study was to investigate the development of korean vowels by acoustically analyzing whether children produce Korean vowels differently according to their age and gender between ages 4 and 6. Methods : A total of 104 children aged 4~6 years (56 males and 48 females) participated in this study. The participants were classified as either 4, 5, or 6 years old. Vowel speech data was obtained by asking the subjects to pronounce meaningful words in which the vowel in question was located in the first syllable. Speech analysis was performed using the Multi-speech 3700 program. Results : Age, gender, and vowel being pronounced all had significant effects on intensity. There was significant decrease with increasing age, and the intensity was significantly higher in male children than female children. Neither age, gender, nor the vowel being produced affected the fundamental frequency. The fundamental frequency produced did not differ by age or gender. The first and second formants had considerable effect on age and vowels, significantly decreased with age, and did not have a gender difference. Conclusion : The results of this study showed that children aged 4~6 have similar anatomical structures, but that maturity of speech motor skills required to pronounce vowels was correlated with age. The results of this study can be used to evaluate children's speech and develop speech therapy programs.

• Proceedings of the KSPS conference
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• 1996.10a
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• pp.207-207
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• 1996

The neutral tone is one of the most important distinguishing features in Beijing Mandarin, but there are two completely different views on its linguistic function: a special tone(Xu, 1980) versus weak stress(Chao, 1968). In this paper, the acoustic manifestation of the neutral tone will be explored to show that it is closely related to weak stress. 122 disyllabic words in which the second syllable carries the neutral tone, including 22 stress pairs, were uttered by a native male speaker of Beijing dialect and analysed by Kay Digital Sonagraph 5500-1. The results of the acoustic analysis are presented as follows: 1) The first two formants of the medial and the syllabic vowel moves towards that of central vowel with a greater magnitude in the syllable with the neutral tone than in the syllable with any of the four normal tones. Also the vowel ending, and nasal coda /n/ and / / in the syllable with the neutral tone tends to be deleted. 2) In the syllables with the neutral tone, there are strong carryover coarticulations between the medial and syllabic vowel and the preceding unvoiced consonant. In general, the vowel is affected to move towards the position of the central vowel with more greater magnitude by coronal consonant than by labial or velar consonant. 3) In the syllable with the neutral tone, when and only when it precedes a syllable with tone-4, the high vowel following [f], [ts'], [s], [ts'], [s], [tc'] or [c] tends to be voiceless. 4) It can be seen from the acoustical results of 22 stress pairs that the duration of the syllable with the neutral tone is on the average reduced to 55% of that of the syllable with the four normal tones, and the duration of the final in the syllable with neutral tone is on the average reduced to 45% of that of the final in the syllable with the four normal tones(Lin & Yan 1980). 5) The FO contour of the neutral tone is highly dependent on the preceding normal tone(Lin & Yan 1993). For a number of languages it has been found that the vowel space is reduced as the level of stress placed upon the vowel is reduced(Nord 1986). Therefore we reach the conclusion that the syllable with neutral tone is related to weak stress(Lin & Yan 1990). The neutral tone is not a special tone because the preceding normal tone.