Most Americans who study music formally do so using common-practice era western tonal theory. Tonal theory is very useful in understanding the music of western Europe in the eighteenth and early nineteenth centuries, and the music derived from it. However, tonal theory is inadequate to explain the blues and other musics of the African diaspora. Given the central role of this music in both popular culture and art music, music theory classes do their students a grave disservice by not discussing its harmonic content.
The blues is based around a very different set of harmonic expectations than the ones underlying classical music. In the blues, major and minor tonality are freely intermingled. Dominant seventh chords can function as tonics. Tritones may or may not resolve. The blues scale is as basic in this context as the major scale is in tonal harmony. We need some new and better vocabulary. In this post, I propose that we teach blues tonality as a distinct category from major or minor, combining elements of both with elements not found in either.
In conventional tonal theory teaching, the major scale is taught as the most basic and fundamental theoretical building block. The very language of tonal theory proceeds from the assumption that the major scale is the most ‘natural’ one. For example, in the key of C major, we modify the ‘natural’ seventh B to produce the ‘flat’ seventh B♭. In the context of western Europeans music, this convention makes good musical sense. But western Europe is not the only salient influence on the musical culture of the United States. The music of the African diaspora is equally fundamental, and it has come to weigh increasingly heavily over time.
African diasporic musical culture expresses itself through all of America’s indigenous music: jazz, rock, hip-hop, R&B, country, and of course, the blues. The music academy gathers all of these genres together under the term ‘popular music’ (with the exception of jazz, which in recent decades has become a ‘legitimate’ art music.) Steven Feld goes so far as to describe American popular music as “a euphemism for Afro-American popular musics” (31). Growing up in America’s popular culture enculturates us with a quite different sense of what ‘natural’ harmony is. For example, DeClerq and Temperley (2011) show that the ♭VII chord is vastly more prevalent in rock than in common-practice classical music. To a lifelong rock listener, B♭ may well sound more ‘natural’ in the key of C than B does.
I propose that we teach blues tonality as a distinct category from major or minor, combining elements of both with elements not found in either. Furthermore, I propose that we present blues tonality as being as fundamental a tonal category as major or minor, rather than as a strange exception. Popular musicians, who tend to be self-taught, already effectively do treat blues this way (Green 2002, 43). The music academy should do the same.