Voice Onset Time (VOT)
Definition
The interval between the release of a stop consonant closure and the onset of vocal fold vibration for the following vowel. VOT values differ systematically between languages, between aspirated and unaspirated categories, and (to a lesser degree) between individuals.
- Full name
- Voice Onset Time
- Measures
- Interval from stop consonant release to vocal fold vibration onset
- Varies by
- Language, aspirated versus unaspirated category
- Individual variation
- Present but smaller than cross-language variation
Common questions
Why does VOT matter more for cross-linguistic casework than for identifying a single speaker?+
Because VOT differences between languages and between aspirated and unaspirated stop categories are large and systematic, VOT is more useful for characterising a speaker's linguistic background or accent than as a stable individual fingerprint, since within-language speaker-to-speaker VOT differences are comparatively small.
Can VOT be measured reliably from poor-quality recorded speech?+
VOT measurement needs a clear stop release burst and voicing onset visible on a spectrogram or waveform, so heavy background noise, low sampling rate, or codec compression common in phone or covert recordings can make accurate VOT measurement difficult or impossible.
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