The other famous Ockeghem star turn is the Missa cuiusvis toni, the “Mass in any mode.” It is notated
without clefs. The singers can decide on one of four different clef combinations, each of which, when
supplied mentally, fixes the notated music on one of the “four finals,” (as described by the chant theorists)
from D to G. When the final is D, the modal scale will be Dorian; when E, Phrygian; when F, Lydian; and
when G, Mixolydian. In Ex. 12-8, the brief opening Kyrie is given all four ways. In order to make the
harmony compatible with any mode, “authentic” cadences—impossible in Phrygian because “on the white
keys” the “dominant” chord to E is diminished—had to be avoided throughout the Mass in favor of
“plagal” ones.
EX. 12-8A Johannes Ockeghem, Missa cuiusvis toni, Kyrie I, pitched on D (Dorian)EX. 12-8B Johannes Ockeghem, Missa cuiusvis toni, Kyrie I, pitched on E (Phrygian)