The perception of English and Thai fricatives and affricates by Thai learners

Abstract

English has eight voiceless-voiced fricatives /f, v, θ, Ð, s, z, ∫, and ȝ/ and two affricates /t∫ and dȝ/ in all positions. Thai, however, carries only two initial voiceless fricatives /f, s/ and one initial voiceless affricate /t∫/. In the literature, the acoustic cues for fricatives include the frication noise, the amplitude, and the fundamental and formant frequencies on the adjacent vowels. This research explores how Thai listeners can perceive the English fricatives and affricates, as opposed to the Thai set. Thirty-one English and fifteen Thai words with fricatives and affricates were chosen. Two native-American male speakers read all English words, and a native-Thai female speaker read all Thai words. All the words were acoustically measured for the acoustic cues and digitally modified for all 312 tokens with different quality and quantity. Twenty native-Thai listeners (14 females and 6 males) listened and identified each token whether it contained which original fricative or affricate. The results revealed that the correct responses of the Thai learners were at a higher rate (90–100%) for the Thai original and modified tokens, and at a lower rate (30–100%) for the English set. It is hoped that this study will shed light on to future perceptual studies.