The experience of rhythm in poetry indicates that the “beat” of a syllable is an important phenomenon in language. Investigators of metrical rhythm have assumed that the physical start of a syllable is the “instant” or its beat. In this study, subjects talked in strict time with a metronome “click.” Measurements were made from sound spectrographic recordings. The “instant” of the syllable is rarely at its start; it is much more usually at or within its vowel section. The evidence best fits the hypothesis that a tension peak in the speaker's vocal muscles is the timing point of a syllable.