Psychometrically equivalent spondaic words spoken by a female speaker

Several studies demonstrate that thresholds for the individual CID W-1 spondaic words peaked at 0 vu are not equivalent. The purpose of this study was to equate the spondaic word thresholds psychometrically. Two studies were performed on 2 groups of 20 listeners with normal hearing. In Experiment 1, psychometric functions were established for the 36 spondaic words spoken by a male (original recording) and female speaker. Based on the threshold data from Experiment 1, the words spoken by the female speaker were adjusted digitally in level to produce equal thresholds (equal intelligibility). In Experiment 2, psychometric functions then were established for the 36 spondaic words adjusted in level. The mean thresholds for the 2 experiments were the same (0.5 dB HL; ANSI, 1996), but the standard deviations for the word thresholds in Experiment 2 (0.7 dB) were significantly smaller than the standard deviations in Experiment 1 (1.6 dB). Both versions of the spondaic words spoken by the female speaker are included on the Speech Recognition and Identification Materials (Disc 2.0) compact disc.