Vowel confusions of hearing-impaired listeners under reverberant and nonreverberant conditions.

The effects of reverberation on the perception of vowels and diphthongs were evaluated using 10 subjects with moderate sensorineural hearing losses. Stimuli were 15 English vowels and diphthongs, spoken between/b/and/t/and recorded in a carrier sentence. The test was recorded without and with reverberation (T = 1.2 s). Although vowel confusions occurred in both test conditions, the number of vowels and diphthongs affected and the total number of errors made were significantly greater under the reverberant condition. The results indicated that the perception of vowels by hearing-impaired listeners can be influenced substantially by reverberation. Errors for vowels in reverberation seemed to be related to the overestimation of vowel duration and to a tendency to perceive the pitch of the formant frequencies as being higher than in vowels without reverberation. Error patterns were somewhat individualized among subjects.