Acoustic Characteristics of Spondee Syllable Stress

Effects of Stress, Stop Release, and Familiarization on Speech Recognition Thresholds

“…A possible propensity was noted in which clinicians tend to increase the f 0 and duration of the second syllable in an effort to produce spondees with equal stress, while maintaining relatively equal amplitude [13]. Thus, "unequal stress" acoustically assumed higher f 0 and longer duration on the second syllable of each spondee than on the first syllable in the creation of R1.…”

“…Despite considerable variability in spondee production across clinicians and the potential theoretical impact on SRT outcomes [13,19,20], no empirical data have been reported in the literature. Meanwhile, prior familiarization, with its well-known effect on SRT outcomes [11,12], has been considered an essential step of the ASHA's guidelines [2].…”

“…and a licensed speech-language pathologist (as an external rater) independently and audibly perceived unequal stress in each word on the R1 list. Inclusion of a perceptual component in the working definition of unequal stress was necessary, given that subtle acoustic inequalities may not be sufficient for a listener to perceive two syllables as being unequal [13].…”

“…Bettagere [13] analyzed stress patterns in a professional recording (Q/Mass Speech Audiometry, Qualitone, 1988) of a spondaic list intended for clinical use. Results from the acoustic analysis demonstrated statistically significant differences between syllables in the measures of duration and f 0 , but not in the measure of amplitude, presumably due to the use of the volume unit (VU) meter monitoring peak syllable levels.…”

“…Spondees, by definition, must be "two-syllable words with equal stress on both syllables" and are typically represented by compound words such as "baseball" [2]. To account for stress discrepancies (i.e., primary versus secondary stress) found in most disyllabic English words, audiologists routinely use calibrated volume unit (VU) meters to ensure that both syllables peak at zero on the VU meter [1,13]. Stress, however, is associated not only with amplitude, but also syllable duration and fundamental frequency (f 0 ) [14,15], with the latter two cited as the dominant features [16].…”