Speech spectra for six recorded monosyllabic word tests

Speech spectra (long-term RMS levels and 1% speech peaks) in third-octave bands were determined for six monosyllabic word test materials: digital recordings of the Central Institute for the Deaf W-22 word test and the Northwestern University NU-6 word test obtained from Qualitone; audiotape recordings of the Central Institute for the Deaf W-22 word test, the Northwestern University NU-6 word test, and the Harvard Psycho-Acoustic Laboratory PB-50 word test obtained from Auditec of St. Louis; and an audio-tape recording of the Maryland CNC word test obtained from Olsen Distributors. The spectra were generally within 2 SD of previous results for continuous speech spoken by an average male talker (Cox, Matesich, & Moore, 1988; Cox & Moore, 1988), but differed sufficiently from those data and from one another to affect the accuracy of Articulation Index calculations. The relationship between the level of the calibration tone and the speech in the third-octave band centered at 1000 Hz was different for each recording.