Cadence (music) - Cadences in Medieval and Renaissance Polyphony

Cadences in Medieval and Renaissance Polyphony

Medieval and Renaissance cadences are based upon dyads rather than chords. The first theoretical mention of cadences comes from Guido of Arezzo's description of the occursus in his Micrologus, where he uses the term to mean where the two lines of a two-part polyphonic phrase end in a unison.

A clausula or clausula vera ("true close") is a dyadic or intervallic, rather than chordal or harmonic, cadence. In a clausula vera two voices approach an octave or unison through stepwise motion. This is also in contrary motion. In three voices the third voice often adds a falling fifth creating a cadence similar to the authentic cadence in tonal music.

According to Carl Dahlhaus, "as late as the 13th century the half step was experienced as a problematic interval not easily understood, as the irrational remainder between the perfect fourth and the ditone:

In a melodic half step, "no tendency was perceived of the lower tone toward the upper, or of the upper toward the lower. The second tone was not taken to be the 'goal' of the first. Instead, the half step was avoided in clausulas because it lacked clarity as an interval." Beginning in the 13th century cadences begin to require motion in one voice by half step and the other a whole step in contrary motion. In the 14th century, an ornamentation of this with an escape tone became known as the Landini cadence, after the composer who used them prodigiously.

A plagal cadence was found occasionally as an interior cadence, with the lower voice in two-part writing moving up a perfect fifth or down a perfect fourth. A pause in one voice may also be used as a weak interior cadence.

In counterpoint an evaded cadence is one where one of the voices in a suspension does not resolve as expected, and the voices together resolved to a consonance other than an octave or unison (a perfect fifth, a sixth, or a third).