15th International Congress of Phonetic Sciences (ICPhS-15)
This paper reports observations and results obtained in an experiment on short and long vowels in Twi, a tone language spoken in Ghana, West Africa. Two adult Twi speakers produced oral and nasal vowels belonging to the two phonological classes. The overwhelming evidence from our acoustic data is that vowel duration is the determining factor in distinguishing the two classes. Acoustic results further show that short and long vowels are distinguished not only by vowel duration but also by post-vocalic consonant duration: phonologically short vowels are followed by phonetically long consonants. Relative values also make clear and further confirm the robustness of the feature in Twi.
Bibliographic reference. Manyah, Kofi Adu (2003): "Vowel quantity contrasts in Twi", In ICPhS-15, 3185-3188.