The mass movements, all for three voices, most often employ the fauxbourdon style, while the motets are typically isorhythmic.
12.
This tended to obscure the rhythm supplied by the " cantus firmus " that had been apparent in the medieval isorhythmic motet.
13.
Structural diagram of the isorhythmic tenor in Johannes Alanus "'Sub arturo plebs Fons citharizantium In omnem terram ".
14.
This is unusual for isorhythmic motets, in which the sections normally become progressively shorter, but this proportional structure achieves its own equally effective balance.
15.
Moreover, the final isorhythmic section provides the usual drive to an accelerated finish by giving the upper voices the shortest note values in the piece.
16.
Two of the era's most important composers of isorhythmic motets are Phillipe de Vitry ( 1291 1361 ) and Guillaume de Machaut ( c . 1300 1377 ).
17.
His motet " A virtutis ignitio / Ergo beata / Benedicta filia ", for four voices with three simultaneously sung texts, is isorhythmic in all parts.
18.
While it grew out of the medieval isorhythmic motet, the Renaissance composers of the motet generally abandoned the use of a repeated figure as a " cantus firmus ".
19.
During the period the motet transformed from the isorhythmic model of the 14th century to the smoothly polyphonic, sectional composition seen in the work of the later Burgundians such as Busnois.
20.
The three mass movements, two Glorias and a Credo, all for four voices, are influenced by Ciconia; the three motets, also for four voices, are isorhythmic.
