I mean 예사소리 (plain), 된소리 (tense), and 거센소리 (aspirated) by "the three types", in regard of voiceless occulsives, of course.
As for voice onset time (VOT), it is well-known that 된소리 (ㄲ,ㄸ,ㅃ,ㅉ) has the shortest, 예사소리 (ㄱ,ㄷ,ㅂ,ㅈ) has the intermediate, and 거센소리 (ㅋ,ㅌ,ㅍ,ㅊ) has the longest. Yet I suspect there are other factors that make this difference.
The particular such factor I believe to exist is the flow velocity (유속; 流速) of the airstream (here I abbreviate to FVA) during the aspiration (that is, between release and voice onset). In this regard, I suspect 예사소리 has slower FVA than 된소리. Was there a study on this?
EDIT: I suspect FVA also distinguishes ㅅ and ㅆ.