It is a widespread opinion that musicians who are interacting together in a performanceshould perfectly synchronize their timing. This view was challenged for the swing feel, asalient feature of jazz, which has eluded scientific clarification for a century. For much of thisperiod it was considered arcane, arguing that swing can be felt but not explained, until atheory of 'participatory discrepancies' raised the controversial claim that swing is caused bymicrotiming deviations between different participating musicians [1] and put a questionmark on the synchronization of jazz musicians.

In several projects we have clarified the controversy on the central role of microtimingdeviations for the swing feel using data analytics [2] and experiments [3,4] in which wemanipulated the timing of different instruments and measured the resulting swing feelthrough ratings of professional jazz musicians. We thereby showed that involuntary randommicrotiming deviations are irrelevant for swing [3], but found that a particular systematicmicrotiming deviation between musicians enhances the swing feel and is a key componentof swing in jazz [4]. It consists in phase shifts, where downbeats of soloists are slightlydelayed with respect to a rhythm section, but offbeats remain strictly in phase.

This effect was unknown to professional jazz musicians, who were able to perceive thedifferences, but unable to determine their nature. Thus musicians apparently use the effectintuitively and unconsciously, as our data analysis of 456 renowned jazz solos revealed theuse of downbeat delays in almost all cases [4].

[1] C. Keil, Cultural Anthropology 2, 275 (1987).

[2] M. Sogorski, T. Geisel, and V. Priesemann, PLoS One 13(1), e0186361 (2018).

[3] G. Datseris, A. Ziereis, T. Albrecht, Y. Hagmayer, V. Priesemann, and T. Geisel,Sci. Rep. 9, 19824 (2019).[4] C. Nelias, E.M. Sturm, T. Albrecht, Y. Hagmayer, and T. Geisel,Commun. Phys. 5, 237 (2022).