Durational and Formantshift Characteristics of Telugu Alveolar and Bilabial Nasal Phonemes

The phonetic-acoustic characteristics of phonemes of a stress-timed language like English and those of syllable-timed Indian languages, are significantly different. Even within the Indian languages, the acoustic characteristics of the phones of a phoneme of one language could be different from those of another language. Significant differences exist in the pronunciations of phones, across Indian languages. Hence the characteristics of a syllable in English or any other Indian language cannot be directly transferred or extrapolated to characterize the similar syllables in Telugu language. There are some results available on acoustic characteristics of Telugu vowels, and very limited results on selective consonant classes. The full set of Telugu consonants yet needs a focused attention. The aim of this paper is to explore some of the acoustic features of the alveolar and the bilabial nasal phonemes. The analysis features include the Nasal murmur duration, spectral envelope, formants, formant tracks and antiformants. The formant tracks laid down on the spectral envelopes are used for detecting the boundaries of nasal murmur. The murmur duration and the shift of formants from murmur into or from the neighboring vowels are quantified for word-initial, word-medial and word-final positions using rank statistics. Box-Jenkinson plots are used for visualization of ensemble statistics of murmur duration and histogram plots for formant shifts. Descriptive analysis is carried put on murmur duration and shifts of first three formants.