How steady are vowel steady-states?

The duration of vowel steady-states (VSS) was examined acoustically in the speech production of 40 normal young adults. VSS was assessed according to formant frequency changes in sustained /i/ productions and consonant +/i/+/d/(/Cid/) productions. The duration of the VSS was measured for the first and second formants (F1 and F2) by incorporating a fixed rate-of-change criterion. Results indicated no significant differences in VSS duration according to gender or vowel context. VSS duration based on F1 was significantly longer than F2 VSS duration. The duration of VSS was also found to be correlated to the overall vowel duration in /Cid/ contexts. Discussion focuses on the analysis and application of VSS in acoustic studies of normal and disordered speech production.