EX. 9-9 Cunctipotens genitor from Faenza CodexThe arrangement of Machaut’s De toutes flours follows the same idea. Ex. 9-10 gives the “A”
section. It adapts Machaut’s tenor as a cantus firmus, meanwhile transposing it up a fifth, lightly
decorating it, and recasting its rhythms from simple-into-compoundduple patterns (or, in Ars Nova terms,
changing the prolation from minor to major). Over it the right hand plays a version of Machaut’s cantus
that is so overgrown with embellishment as to be scarcely recognizable. (It is easiest to recognize at the
musical rhyme: compare Ex. 9-10 at mm. 23 ff and 56 ff with the corresponding passages of Ex. 9-8.)
This arrangement (or intabulation, as arrangements for keyboard are often called) is extremely
suggestive. It gives us grounds for surmising what instrumental virtuosos did at a time when practically no
instrumental music was written down. Instrumental music, too, started out as an “oral” culture, if the term
oral can be expanded to encompass the digital, based on listening, practicing, and emulating; and it left
few traces before the sixteenth century for historian-sleuths to interpret. A book like the Faenza Codex,
therefore, is a precious document. It reveals the way in which “standard”—or “classic”—vocal
compositions may have provided highly skilled instrumentalists (like today’s—well, yesterday’s—jazz
virtuosos) with a repertoire for specialist improvisation.