Voicing: when the vocal folds start

Japanese contrasts voicing, not aspiration: か vs が differs in how soon after the burst the vocal folds start vibrating (VOT).

Minimal pairs

Click a cell to compare clear and voiced.

or use the + on each cell

Minimal pairs in sentences

Two sentences side by side, differing by one sound in the same slot. Tap a card to hear the whole line, tap the highlighted part to hear just that.

Measured VOT

Shorter VOT = voiced; longer VOT = voiceless aspirated.

KanaRomajiTypeSpeakerDurationVOTVoiced ratio
かkaclearfemale190 ms32 ms63%
かkaclearmale160 ms132 ms12%
がgavoicedfemale170 ms21 ms68%
がgavoicedmale180 ms37 ms61%
さsaclearfemale270 ms126 ms37%
さsaclearmale180 ms117 ms22%
ざzavoicedfemale230 ms1 ms67%
ざzavoicedmale230 ms17 ms76%
たtaclearfemale130 ms16 ms68%
たtaclearmale150 ms42 ms23%
だdavoicedfemale150 ms16 ms70%
だdavoicedmale180 ms17 ms86%
はhaclearfemale220 ms66 ms57%
はhaclearmale180 ms–0%
ばbavoicedfemale160 ms2 ms81%
ばbavoicedmale190 ms37 ms62%
ぱpasemifemale180 ms11 ms72%
ぱpasemimale140 ms52 ms21%

Which pairs actually separate

Rule: a voiced VOT at least 10 ms shorter than its clear counterpart. Computed from the data — the female た/だ pair does not separate here, and the page says so.

pairfemalemale
か / がseparatesseparates
さ / ざseparatesseparates
た / だno gapseparates
ば / ぱno gapseparates

How to practise

Where these numbers come from

VOT = speech-span start → first voiced frame; voiced ratio = voiced frames / frames in the span, both from parselmouth on normalised synthesis.

Synthesis VOT is an engine value: compare relatively; real speech varies with rate.