Perceptual (aural) and spectrographic investigation of speaker homogeneity

Abstract

In order to investigate the perceptual and spectrographic homogeneity of speakers, 28 (14 pairs) talkers recorded an extended prose passage on two occasions, one week apart. Twelve talkers were chosen as six pairs on the basis of their having been confused with each other due to the similarity of their voices. A tape was prepared for the presentation of two randomized 2-sec speech segments for each pair of talkers. Listeners made aural/perceptual judgments of same or different for the following conditions: (1) same/contemporary (i.e., one talker recorded at the same time); (2) same/noncontemporary (i.e., one talker recorded one week apart); (3) different (i.e., paired talkers). Preliminary analysis of the data indicate the following: (1) 96% correct identifications were obtained for the same talker paired with a contemporary speech segment; (2) 44% correct identifications were obtained when comparing the same talker with a noncontemporary speech sample; (3) 87% correct identifications were obtained when comparing different talkers of a pair; (4) confusions between contemporary and noncontemporary samples of talker pairs occurred at a 38% level. High identification scores were expected for categories 1 and 3. It is evident that correct identification of a talker drops sharply when the comparison speech sample is noncontemporary. Further research duplicated the above procedure utilizing the same speech samples filtered to match a telephone passband; results were similar to the above. Spectrographic matching will be done for both procedures and results from each will be correlated.