Acoustical Characteristics of the Cantonese Vowels and Tones Produced by Hearing Impaired Speakers

The paper investigates the acoustical characteristics of the Cantonese vowels and tones produced by three male and three female hearing impaired (HI) speakers with cochlear implants or hearing aids. The vowels and tones produced by two speakers of normal hearing (NH) are also analysed for comparison purposes. Results show all the six HI speakers differentiate the durations of (a) long, (b) medium-long and (c) short vowels in Cantonese. While the HI speakers differ from the NH speakers in absolute vowel durations, the ratios of (a):(b) and (b):(c) for the HI speakers are comparable to those for the NH speakers. The vowel loop data show the HI speakers with cochlear implants (CI) perform almost as equally well as the NH speaker and outperform the HI speakers with hearing aids (HA) in the production of the Cantonese vowels. The HA speakers produce the vowel loops of reduced sizes compared to those produced by the NH speakers. The F0 curves show the HA speakers outperform the CI speakers in the production of the Cantonese tones. It appears there is a correlation between the type of HI speakers and the production performance of vowels or tones.