Eight female trainees from National Institute of Education (NIE), representing the four major ethnic groups in Singapore, were involved in this study. Although it has been said that female speech is much harder to analyse than male speech, it was possible to measure these vowels using the latest technology i.e., computer-based software.
Four selected English vowels were examined. They are monophthong pair /ae/ and /e/, and diphthongs /eI/ and /eu/. These vowels were selected because it is claimed by many researchers that the two monophthongs are conflated in Singapore English and that the two diphthongs are produced as long monophthongs rather than diphthongs. However, these claims were mostly based on auditory perception and not on instrumental analysis. Hence, this study aimed to verify these claims through using the Computer Speech Lab (CSL) software by Kay.
This study also compares the four vowels in three different levels of situations: very formal situation (citation form), formal situation (subjects talking to a British lecturer), and informal situation (subjects talking to the researcher). These vowels were also compared to the RP vowels.
Results show that the SE speakers are capable of distinguishing /ae/ and /e/ in citation form. However, in both types of conversation, there is much less distinction between the pair. When the values obtained are plotted on the vowel quadrilateral chart, it is found that the conversational vowels are more centralised and located almost at the same position on the chart.