Changing phonation [p] followed by [a] [p] is voiceless [a] is voiced The switch from voiceless to voiced could happen two ways Voicing could coincide with the release of [p] Voicing could be delayed till after the release
Which is which? voicing coincides with release voicing is delayed till after release (Catford figure 18)
VOT (voice onset time) The time between the closure release and the beginning of voicing Voicing coincides with closure release Zero VOT Voicing delayed till after closure release Positive VOT
VOT
Negative VOT [b] followed by [a] In English, slightly negative In French, very negative Fully voiced stop
Aspiration A puff of air between the release of the closure and the onset of voicing Please study this website: http://www.phon.ucl.ac.uk/home/johnm/siphtra/plostut2/plostut2.htm