Rainer Polak

Both Isochronous and Non-Isochronous Metrical Subdivision Afford Precise and Stable Ensemble Entrainment: A Corpus Study of Malian Jembe Drumming.

Most approaches to musical rhythm, whether in music theory, music psychology, or musical neuroscience, presume that musical rhythms are based on isochronous (temporally equidistant) beats and/or beat subdivisions. However, rhythms that are based on non-isochronous, or unequal patterns of time are prominent in the music of Southeast Europe, the Near East and Southern Asia, and in the music of Africa and the African diaspora. The present study examines one such style found in contemporary Malian jembe percussion music. A corpus of 15 representative performances of three different pieces (“Manjanin,” “Maraka,” and “Woloso”) containing ~43,000 data points was analyzed. Manjanin and Woloso are characterized by non-isochronous beat subdivisions (a short IOI followed by two longer IOIs), while Maraka subdivisions are quasi-isochronous. Analyses of onsets and asynchronies show no significant differences in timing precision and coordination between the isochronously timed Maraka vs. the non-isochronously timed Woloso performances, though both pieces were slightly less variable than non-isochronous Manjanin. Thus, the precision and stability of rhythm and entrainment in human music does not necessarily depend on metric isochrony, consistent with the hypothesis that isochrony is not a biologically-based constraint on human rhythmic behavior. Rather, it may represent a historically popular option within a variety of culturally contingent options for metric organization.

Rhythm histograms and musical meter: A corpus study of Malian percussion music

Studies of musical corpora have given empirical grounding to the various features that characterize particular musical styles and genres. Palmer & Krumhansl (1990) found that in Western classical music the likeliest places for a note to occur are the most strongly accented beats in a measure, and this was also found in subsequent studies using both Western classical and folk music corpora (Huron & Ommen, 2006; Temperley, 2010). We present a rhythmic analysis of a corpus of 15 performances of percussion music from Bamako, Mali. In our corpus, the relative frequency of note onsets in a given metrical position does not correspond to patterns of metrical accent, though there is a stable relationship between onset frequency and metrical position. The implications of this non-congruence between simple statistical likelihood and metrical structure for the ways in which meter and metrical accent may be learned and understood are discussed, along with importance of cross-cultural studies for psychological research.

Kulturelle Diversität in der empirischen Rhythmusforschung: Drei Analysen eines Audio-Korpus von Percussion-Ensemblemusik aus Mali

Die Erorterung kultureller Varianz sowohl zwischen als auch innerhalb von Gesellschaften leidet unter der Neigung, das je eigene kulturelle Umfeld als ›naturlich‹ wahrzunehmen. Diese Neigung ist in der Musikforschung nicht zuletzt als eurozentrisches Bias nach wie vor prasent. Unser Artikel mochte zu punktuellen Korrekturen dieses Bias im Feld der empirischen Rhythmusforschung beitragen. Wir analysieren einen Korpus von Audio-Aufnahmen aus Mali und untersuchen dabei das Verhaltnis von Rhythmus und Metrum (Studie 1), den theoretischen Status ungleichmasiger Grundschlagsunterteilung (›Swing-Timing‹, Studie 2) und die Interaktion musikalischer Rollen bei der Ensemble-Synchronisation (Studie 3). Discussions of cultural variation, both between and within societies, suffer from the disposition to conceive of one’s own cultural environment as ›natural.‹ This disposition is still present not least as a euro-centric bias in the study of music. Our article strives to offer a partial correction to the lingering euro-centric bias in the field of empirical rhythm research. We analyze a corpus of audio recordings from Mali, wherein we study three issues: rhythm-meter relations (study 1), the theoretical status of uneven beat subdivision or ›swing timing‹ (study 2), and the interaction amongst musical roles in ensemble synchronization (study 3).