Conventional and characteristic harmonic sequences across Brazilian choro, Western classical music and rock: tonal harmony in a Global South context

Abstract

Data-driven research on different harmonic styles, including both Western classical and popular music, has increased substantially since the early 2000s (e.g. de Clercq and Temperley, 2011, Broze and Shanahan, 2013, Devaney et al., 2015, de Clercq, 2022). Such studies have largely focused on a single style at a time, while also rarely addressing styles from the Global South. Sears and Forrest (2021) present a method for comparing Western classical and rock harmonic styles based on large corpora of Roman numeral annotations (namely, the ABC, TAVERN, Rolling Stones and McGill Billboard corpora), ranking both the conventional chord progressions of each style (i.e. those most commonly found in the style) as well as the characteristic progressions (i.e. those that are unique to a style or corpus relative to a comparison style, or anti-corpus). The present study addresses the lack of representation of styles from the Global South by reproducing the methodology of Sears and Forrest with the inclusion of Brazilian choro, based on the corpus by Moss et al. (2019), which contains harmonic annotations of 295 choro pieces. We identify the most conventional tri-grams of Roman numeral sequences in choro and the most characteristic in comparison to the Western classical and rock databases used in the original study. Preliminary results indicate that choro harmony, even if largely tonal and tertian, exhibits unique chord progressions at formal boundaries relative to the other two styles, such as iv - iiø - i (relative frequency ratio = 5.58 relative to classical, and 6.47 relative to rock). These results advance our knowledge of how a previously under-studied genre deploys unique vocabularies of tonal chord progressions in comparison to more studied styles, increasing our understanding of how tonal harmony develops in different parts of the world and contributing to diversity in corpus studies (Shea et al. 2024).

Fabian C. Moss

Digital Music Philology and Music Theory

Fabian C. Moss is an assistant professor for Digital Music Philology and Music Theory at Julius-Maximilians University Würzburg (JMU), Germany.