interonset interval

In music the interonset interval or IOI is the time between the beginnings or attack-points of successive events or notes, the interval between onsets, not including the duration of the events. For example, two sixteenth notes separated by dotted eighth rest would have the same interonset interval as between a quarter note and a sixteenth note. The concept is often useful for considering rhythms and meters. (London 2004, p.4)
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