English lexical stress is multidimensional in nature and acoustically related to combination of fundamental frequency (F0), duration, intensity and vowel quality. Errors in any or all of these correlates could interfere with perception of the stress contrast, but it is unknown which correlates are most difficult for Bengali speakers to acquire. This study compares the use of these correlates in the production of English lexical stress contrasts by 10 L1 English and 20 L1 Bengali speakers. Results showed that although Bengali speakers used all four acoustic correlates in similar manner like English speakers, but they produced significantly less native like stress patterns. English speakers reduced vowel duration significantly more in the unstressed vowels compared to Bengali speakers and degree of intensity and F0 increase in stressed vowels by English speakers was higher than that by Bengali speakers. There were also significant differences in formant patterns across speaker groups, such that Bengali speakers produced English like vowel reduction in certain unstressed syllables, but in other cases Bengali speakers have tendency to either not reduce or incorrectly reduce vowels in unstressed syllables. Results suggest that Bengali speakers' production of English lexical stress contrast is influenced by L1 language experience and L1 phonology.
Bibliographic reference. Saha, Shambhu Nath / Mandal, Shyamal Kr. Das (2015): "Study of acoustic correlates of English lexical stress produced by native (L1) bengali speakers compared to native (L1) English speakers", In INTERSPEECH-2015, 815-819.