Vocal fold vibration and phonation start in aspirated, unaspirated, and staccato onset

Singers learn to produce well-controlled tone onsets by accurate synchronization of glottal adduction and buildup of subglottal pressure. Spectrographic analyses have shown that the higher spectrum partials are present also at the vowel onset in classically trained singers' performances. Such partials are produced by a sharp discontinuity in the waveform of the transglottal airflow, presumably produced by vocal fold collision.

After hearing a prompt series of a triad pattern, six singer subjects sang the same triad pattern on the vowel /i/ (1) preceded by an aspirated /p/, (2) preceded by an unaspirated /p/, and (3) without any preceding consonant in staccato.

Using high-speed imaging we examined the initiation of vocal fold vibration in aspirated and unaspirated productions of the consonant /p/ as well as in the staccato tones.

The number vibrations failing to produce vocal fold collision were significantly higher in the aspirated /p/ than in the unaspirated /p/ and in the staccato tones. High frequency ripple in the audio waveform was significantly delayed in the aspirated /p/.

Initiation of vocal fold collision and the appearance of high-frequency ripple in the vowel /i/ are slightly delayed in aspirated productions of a preceding consonant /p/.