Relative Timing and Voicing in Arabic Stops: Evidence from the Closure-to-Vowel Ratio

This study investigates the closure-to-vowel ratio (CVR) as a primary, rate-normalized temporal cue to voicing in Arabic stops, within the framework of the Hyper–Hypo theory of speech adaptation and Articulatory Phonology. A sample of 30 Arabic speakers of the Saudi dialect was selected to produce voiced and voiceless stops at normal and fast speech rates. The words considered for analysis were disyllabic and analyzed acoustically to measure the stop-closure duration and the duration of the following vowel. The speech rate, place of articulation, and effects of voicing were analyzed via Linear mixed-effects models. Results showed a strong main effect of voicing, with voiced stops exhibiting significantly lower CVR values than voiceless stops. Across places of articulation, the voicing contrast was identical. The CVR was a fixed, rate-robust temporal mark of distinction of voicing in Saudi Arabic stops. Consistent timing between oral closure and the following vowel in utterers’ speech was observed even in cases of reduced articulation, supporting the notion of adaptive speech production and coordinated gestures. Overall, the study highlights the importance of relational timing in shaping phonological contrast. In the realm of phonetic research, voicing contrast in stops is better conceptualized as a matter of relative temporal mechanism rather than absolute durational differences. Several limitations leave room for future research.