• Phonetics and Speech Sciences
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• v.5 no.3
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• pp.11-20
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• 2013

The purpose of this study is to compare the acoustic parameters of English stop consonants at the initial and after-initial-/s/ positions in a message produced by 47 Korean and American speakers in order to provide better pronunciation skills of English stops for Korean learners. A Praat script was developed to obtain voice onset time (VOT), maximum consonant intensity (maxCi), and rate of rise (ROR) from six target words with stops at the positions in the message. Results show that VOT and maxCi were significantly different between the two language groups while ROR wasn't. The Korean speakers generally produced the stop consonants with longer VOTs and higher consonant intensity. From the comparison of consonant groups at the two different positions, the Korean participants did not distinguish them as clearly as the American participants did at the after-initial-/s/ position. Finally a comparison of each language and sex group revealed that the major difference was attributed to stop consonants in the after-/s/ position. The author concluded that Korean speakers should be careful not to produce all the stops with longer VOTs and higher intensity. Further studies would be desirable to examine how Americans evaluate Korean speakers' English proficiency with modified acoustic values of English stops.

• Speech Sciences
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• v.10 no.2
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• pp.207-221
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• 2003

Phonetic voicing does not support the phonological distinction of voiced/voiceless in English stops. The present study is aimed at defining the nature of voicing of English voiced stops. A review of the literature reveals that the voicing is position-conditioned and its length is notably inconsistent relative to the closure duration. No consistent relationships are found between vocal fold adduction and glottal pulsing in initial position. Stress reduced the voicing, etc. The hypothesis for experiments was: (1) active voicing: stress generates longer (stronger) voicing during the closure duration of a voiced stop; (2) passive voicing: stress induces shorter (weaker) voicing during the closure. Instead the voiced stop becomes more voiced when the preceding vowel (syllable) is stressed. The literature review and the results of two experiments comparing English and Slovakian suggested that the voicing of English voiced stops is passive (i.e., a coarticulation of glottal pulsing for adjacent vowels-syllables) and should be distinguished from active voicing in some other languages.

• Phonetics and Speech Sciences
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• v.3 no.3
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• pp.3-10
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• 2011

This study examined the production of aspirated stop consonants in Korean and English words to address how the influences differed particularly in terms of proficiency in L2 English. Voice onset times (VOTs) were measured from two American monolinguals and seven Korean speakers. The results showed that VOT patterns for both L1 and L2 stops differed according to their proficiency in L2 English. In L2 English, high proficient speakers produced VOTs that were similar to those of native speakers of English whereas low proficient speakers produced VOTs that were significantly longer than those of proficient speakers. In L1 Korean and L2 English, most of the proficient speakers produced VOTs similarly. Unlike previous findings, Korean VOTs were even shorter than English counterparts. The VOT shortening of aspirated stops in Korean was found for most of the proficient speakers. The findings of the present study suggest that cross language phonetic influences as well as the ongoing VOT shortening in Korean aspirated stops may be correlated with L2 proficiency. Since this is a pilot study with a small number of subjects for each proficiency group, further quantitative study is necessary to generalize.

• Phonetics and Speech Sciences
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• v.6 no.3
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• pp.121-130
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• 2014

This study investigates the acoustic property of aspiration realized in English voiceless stops of /Cr/ and /sCr/ clusters. VOT is measured from stops in these clusters produced by two groups; one from native speakers of English and the other from Korean native speakers. Aspiration of stops in different types of clusters is compared to various phonological factors such as location of stress, syllable type, and position in word. Pursuing the idea that phonetic realization is correlated with phonological representation, attempts are made to account for the gradient nature of aspiration of stops on the basis of syllable structure at the phonetic level, which may vary in the wake of resyllabification. Voiceless stops in /Cr/ and /sCr/ clusters are further compared to results obtained in the previous study on /sC/ cluster. Variations in aspiration are also characterized in terms of segmental precedence relation of stops in the clusters, namely, post-[s], pre-[r], or both.

• Phonetics and Speech Sciences
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• v.7 no.3
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• pp.99-105
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• 2015

The current study investigates whether Korean-speaking adults show differential sensitivities to the sources of auditory stimuli (L1 Korean and L2 English) in utilizing VOT and f0 in the perceptual mode of L2 stops, and how the L2 proficiency interacts with the learners' low-level phonetic sensitivities in L2 perceptual mode. 48 Korean learners of English participated in the perception experiments where they rated the goodness of English /t/ and /d/ using an analogue scale. Two sets of stimuli (English and Korean sources) were prepared by manipulating VOT (6-steps) and f0 (5-steps) values of productions by an English male (L2 source condition) and a Korean male (L1 source condition). Findings showed that, in judging /t/-likeness, the listeners responded differently to the two auditory stimulus conditions by relying on VOT significantly more in English source condition than in Korean source condition. The listeners' English proficiency did not interact with these differential sensitivities to the auditory stimulus source either along the VOT dimension or the f0 dimension. The results of the current study suggest that low-level contextual information of the auditory source can affect the learners in faithfully being in the L2 perceptual mode.

• Proceedings of the KSPS conference
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• 2003.10a
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• pp.43-49
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• 2003

This study reveals the perceptual role of stop release burst to Koreans' recognition of POA(place of articulation) and voicing in the English word-final stops. 10 Korean subjects participated in a perception experiment wherein the stimuli are prepared on the basis of the amount of acoustic information, which includes the release burst. The result shows that i) release burst plays an important role in the recognition of POA in the order of velar, alveolar, and bilabial stops, and ii) the release burst more enhances the correct recognition of voiceless stops than that of voiced stops. This result leads us to conclude that the role of stop release burst differs with respect to the POA and voicing of the stops, and it is possibly related to the different intensity of release in voicing and in each POA.

• Phonetics and Speech Sciences
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• v.7 no.3
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• pp.13-26
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• 2015

Speech production studies have suggested that bilinguals who are L2-dominant are the most likely to suppress the influence of the first language (L1) on the second language (L2). The voice onset times (VOTs) and fundamental frequencies (f0s) of monolingual and bilingual speakers of English and Korean were examined to address the question whether cross language influences occur particularly in L2 predominant bilinguals and to compare their outcomes with those of L2 proficient bilinguals and monolinguals. A total of 28 speakers participated in this experiment and they produced English and Korean stops in the carrier sentence. In English, for voiceless aspirated and unaspirated stops, L2 predominant bilingual speakers produced VOTs that were significantly shorter than those of monolingual English speakers. The outcome was analogous in Korean speech. For aspirated and lax stops, they produced shorter Korean VOTs than monolingual speakers. The results of f0s were slightly different from those of VOTs. In English, L2 predominant bilinguals produced f0s that were not significantly different from those of monolingual English speakers. In Korean, however, they produced f0s that were significantly different from those of monolingual Korean speakers. Taken VOT and f0 into consideration together, the overall results suggest that, although they tend to show a corresponding pattern of monolinguals, L2 predominant bilinguals had cross language phonetic influences between L1 and L2, similar to L2 proficient bilinguals. Between the two acoustic cues, f0 seemed to be a more reliable cue than VOT to examine the influences.

• Speech Sciences
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• v.2
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• pp.149-158
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• 1997

An Electropalatographic (EPG) study was made to investigate the articulatory distinction of three series of Korean stops according to tensity and the articulatory mechanism associated between tensity and coarticulatory effects. The results indicated that tensity of Korean stops is closely related to contact width and duration of complete closure, and that coarticulatory vocalic effects vary inversely with the degree of contact width and duration of complete closure.

• Phonetics and Speech Sciences
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• v.1 no.3
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• pp.19-28
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• 2009

This paper reports experimental findings about the duration feature of the acoustic components of English stops in Korean speakers' voicing perception. In our experiment, 35 participants discriminated between recorded stimuli and digitally transformed stimuli with different duration features from the original stimuli. 72 sets of paired stimuli are generated to test the effects of the duration feature in various phonetic contexts. The result of our experiment is a complicated cross-tabulation with 540 cells defined by five categorical independent variables plus one response variable. To find a meaningful generalization out of this complex frequency table, we ran logit log-linear regression analyses. Surprisingly, we have found that there is no single effect of the duration feature in all phonetic contexts on Korean speakers' perception of the voicing contrasts of English stops. Instead, the logit log-linear analyses reveal that there are interaction effects among phonetic contexts (=C), the places of articulation of stops (=P), and the voicing contrast (=V), and among duration (=T), phonetic contexts, and the places of articulation. To put it in mathematical terms, the distribution of the data can be explained by a simple log-linear equation, logF=${\mu}+{\lambda}CPV+{\lambda}TCP$.

• Phonetics and Speech Sciences
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• v.5 no.3
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• pp.31-38
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• 2013

This study investigated the influence of English vowel pronunciation training to English word-initial stop pronunciation. For that purpose, VOT values of English stops produced by twenty Korean English learners(five Youngnam dialect male speakers, five Youngnam dialect female speakers, five Kangwon dialect male speakers, and five Kangwon dialect female speakers) were measured using the Speech Analyzer and their post-training production was compared with their pre-training production. The result shows that post-training VOT values of voiced stops became closer to those of native English speakers in all four groups. Hence, it can be inferred that vowel pronunciation training is effective for correcting pronunciation of voiced vowels by analyzing the change of the quality of following vowels(especially low vowels) and the degree of giving stress.