There are systematic deviations in acoustic measurements of the syllable onsets of perceptually isochronous rhyming monosyllables differing in initial consonant structure [C. Fowler and L. Tassinary, Atten. Perform.IX,521–535 (1981)]. In the present study we examine the corresponding intervals of monosyllables that differ in (1) vocalic nucleus or (2) coda. Metronome‐timed tokens of both alliterative and homophonous sequences were measured from the productions of two talkers. The observed intervals between syllable onsets and those between vocalic onsets show a pattern consistent with the hypothesis that talkers and listeners are sensitive to a syllable‐internal event, perhaps the articulatory onsets of the vowels. [Work supported by NICHHD.]