Acoustic investigation of English and Japanese [s] and [θ] by English and Japanese speakers

It has been said that there are certain differences between English /s/ and Japanese /s/ in their articulation, and also in their auditory impression that the former sounds stronger than the latter. This paper is trying to reveal the differences/similarities of the acoustic characteristics of English and Japanese voiceless alveolar fricatives in their L1 and L2 speech and to know how the articulatory differences and the auditory impression would be reflected in acoustical properties such as their amplitude, duration, formant frequency, and spectral shape.

Three native British English speakers whose L2 is Japanese, and three native Japanese speakers whose L2 is English were asked to read out word lists in their first and second languages. As a result, it was found that there was an interesting prominence in the lower frequency region of the spectral shape that can be seen only in the spectra of alveolar fricatives uttered by the English speakers but not in those uttered by the Japanese speakers.