An Acoustic Investigation of The Duration of Vowel Nasalization in Ga

Abstract

Relationship between vowel quality and nasalization has seen a number of investigations in languages with results indicating that the duration of nasalization varies with the quality of vowel. While some of the investigations reported that greater velopharyngeal opening occurs in mid-high and high back vowels in some languages, other investigation results show that low vowels are nasalized with greater velopharyngeal opening than high vowels in some other languages. It has been argued that in vowel nasalization low vowels are preferred because low vowels have longer duration in that long vowels are more likely to be nasalized than short vowels. This study sets out to investigate the relationship between the quality of vowels and nasalization in Ga by using acoustic measures. The study makes use of four native Ga speakers’ production of oral and nasal vowels in words. The words were recorded in a carrier frame and was analysed using PRAAT. The results indicate that nasal vowels have longer duration than oral vowels and the nasal part of the nasal vowel is longer in high vowels than it is in the low vowels. Generally, the nasal portion of the nasal vowel has longer duration than the oral portion of the vowel. Also, the Front vowels seem to have longer nasal portions than the back vowels. Another observation from the analysis was that the nasal vowels have higher F1 and F2 values than the oral vowel. Thus, the amount of nasalization in Ga vowels is influenced by the quality of vowel.