Perception of English minimal pairs in noise by Japanese listeners: does clear speech for L2 listeners help?

This study investigates the effect of different types of clear speech on cross-linguistic perception. In particular, it examines whether the words produced to help L2 interlocutors are perceived more easily by them than the words produced for L1 interlocutors to counteract speech babble noise. English keywords in these conditions are extracted from the LUCID corpus, and they are presented to Japanese listeners for the identification of the words in a minimal pair, in babble noise or without noise. The results demonstrate that when presented in noise, the words produced to help L2 interlocutors are generally perceived more easily by them. This suggests that speech production varies according to listeners’ needs in a specific communicative situation. The strong effect of the acoustic characteristics of Japanese /b/ on the perception by Japanese L1 listeners is also discovered. Further acoustic and perceptual research is required to investigate whether a universal or specific cue-enhancement is involved in the clear speech for L2 listeners.