Fourteenth-century French secular polyphony and the problem of tonal structure

The concept of tonal structure, a particular concern of early music analysts, is a 20th-century construct, which sets out to describe the hierarchical relationship of pitches and sonorities in a polyphonic work. Although fourteenth-century writers do not undertake the topic of tonal structure in polyphonic music, contemporaneous theories can guide us to historically informed analytic methodologies that bear on the perception of tonal structure. This study uses such methodologies, in conjunction with modern methods of empirical analysis, to counter recent theories and to identify procedures which contribute to the construction of tonal structure in individual songs in the secular polyphony of Guillaume de Machaut (c.1300–1377). In contrast to a “single key” approach to tonal structure in fourteenth-century music, I argue for the possibility of multiple tonal centers within individual songs and examine the role of chromatic inflections and cadential goals in delineating tonal structure. All available chromatic inflections can help to define tonal structure contrapuntally by increasing the tendency in directed progressions. Moreover, when chromatic inflections appear melodically, outside the skeletal frame of the contrapunctus, they can still have an impact on the definition of tonal structure by privileging the individual pitches they decorate. The tonal function of cadences is dependent upon the type of cadential progression and concluding sonority. Cadences can be assigned to one of two main types: perfect-sonority cadences and imperfect-sonority cadences. Perfect-sonority cadences with ascending semitone motion in at least one voice are the strongest progressions, while perfect-sonority cadences with descending semitone motion in one voice appear to be weaker or less conclusive tonally. The imperfect-sonority, in addition to its role as a penultimate sonority in a directed progression, can serve a special role in the tonal structuring of a song as a cadential arrival point, simultaneously suggesting repose (through textual position, rhythmic length and mensural placement) as well as continuation and anticipation (through descending semitone motion and intervallic structure). Further, although many features of syntax function in the same way across all genres, formal characteristics can directly affect perception of tonal structure.