Effects of Speaking Rate and Sonority on Voicing Duration in Russian Obstruents

Research has found that temporal cues to obstruent voicing in aspirating languages, e.g. VOT or closure voicing, are affected by context, e.g. speaking rate or phonetic environment. However, little is known about effects of phonetic context on acoustical properties of word-medial obstruents in true voice languages. The present study investigates changes in duration of glottal pulses in Russian word-medial obstruents. The data come from 14 Russian speakers, who pronounced phrases with 2165 voiced and voiceless obstruents before segments with low and high sonority in the slow and fast speaking rate conditions. The findings provide empirical evidence that duration of glottal pulsing in voiced obstruents increases in response to sonority of adjacent segment and at slow speaking rate. The findings reveal that the maximum increase (57 ms) was found in prevocalic position at slow rate, suggesting sonority and speaking rate may feed one another to enhance glottal pulsing in voiced obstruents.