Intelligibility of average talkers in typical listening environments

Abstract

Intelligibility of conversationally produced speech for normal hearing listeners was studied for three male and three female talkers. Four typical listening environments were used. These simulated a quiet living room, a classroom, and social events in two settings with different reverberation characteristics. For each talker, overall intelligibility and intelligibility for vowels, consonant voicing, consonant continuance, and consonant place were quantified using the speech pattern contrast (SPAC) test. Results indicated that significant intelligibility differences are observed among normal talkers even in listening environments that permit essentially full intelligibility for everyday conversations. On the whole, talkers maintained their relative intelligibility across the four environments, although there was one exception which suggested that some voices may be particularly susceptible to degradation due to reverberation. Consonant place was the most poorly perceived feature, followed by continuance, voicing, and vowel intelligibility. However, there were numerous significant interactions between talkers and speech features, indicating that a talker of average overall intelligibility may produce certain speech features with intelligibility that is considerably higher or lower than average. Neither long-term rms speech spectrum nor articulation rate was found to be an adequate single criterion for selecting a talker of average intelligibility. Ultimately, an average talker was chosen on the basis of four speech contrasts: initial consonant place, and final consonant place, voicing, and continuance.

The contribution of changes in F0 and spectral tilt to increased intelligibility of speech produced in noise

“…While several researchers (e.g. Cox et al, 1987;Jones et al, 2007) have demonstrated that slower speaking rates lead to increased speech intelligibility in noise, Sommers (1997) failed to find a perceptual correlate of speaking rate for young listeners with normal hearing. In addition, Bond and Moore (1994) and Hazan and Markham (2004) observed that words with longer duration led to an increased intelligibility in the presence of noise while no such effect of word duration was found in Uchanski et al (2002).…”

Audibility-Index Predictions of Normal-Hearing and Hearing-Impaired Listeners’ Performance on the Connected Speech Test

“…spectrum measured by Cox, Alexander, and Gilmore (1987a), which was not derived from any of the passages in the CST.…”

Perceptual adaptation and intelligibility of multiple talkers for two types of degraded speech

“…Instead, a variety of research findings suggest that speech intelligibility is also influenced by properties of the listener ͑e.g., Bent and Bradlow, 2003;Imai et al, 2003;Labov and Ash, 1997;Mason, 1946͒ and linguistic context ͑e.g., Healy and Montgomery, 2007͒, as well as interactions among these factors ͑e.g., Moore, 2003;Rogers et al, 2006͒. Whether differences across talkers are maintained under different listening environments is an issue that has not been extensively studied. In one of the few extant studies, Cox et al ͑1987͒ found that relative intelligibility rankings among six talkers were generally maintained across four levels of noise degradation ͑speech mixed with babble͒. More recently, Green et al, ͑2007͒ reported no differences in talker intelligibility among three groups of listeners: normalhearing listeners, CI listeners, and simulated CI listeners.…”