Measurement of Formant Frequency in /hVd/ Words of Distorted Speech in Adult New Zealanders

This paper investigates the acoustic features of distorted speech in adult New Zealanders. There are total of sixteen subjects in this study: eight healthy individuals as control group and eight patients, four of them suffer from non-neurological dysphonia hence, their voice is hoarse but they have not undergone any surgery whereas the other four have gone through total laryngectomy and use a voice prosthesis (TEP) to speak. Building upon our previous work on temporal acoustic characteristics of distorted speech, analysis of the two formant frequencies of vowel articulation in /hVd/ words are presented in this paper. The results of both TEP speech and dysphonic speech are compared to the samples collected from healthy control group.Independent sample t-tests have been carried out once between TEP speech and normal speech, and once between dysphonic and normal speech to show how significant the differences in acoustic measurements are. The results show that formant frequencies in TEP speech are significantly different from normal speech whereas in patients with dysphonia these variabilities are not as notable.