Abstract
Adult normal speech and adult cleft palate speech were acoustically analyzed with respect to vowels. The purpose was to discover a possible correlation between the acoustic features of cleft palate hypernasality and the criteria for auditory judgements of hypernasality. Comparison was made between the results of the above analysis and auditory hypernasality judgements by speech therapists.
The results are as follows: (1) Different formant frequencies were found with respect to vowels and each formant between normal speech and cleft palate speech. (2) On an average, /i/ had lower second and third formants in cleft palate speech, while /u/ had higher values in cleft palate speech with respect to the second and third formants. (3) For some male cleft palate speakers, correlations were found between the acoustic analysis and auditory judgements with respect to the first and second formatns of /a/, the second and the third formants of /i/, and the first formant of /u/.
