Music in pictures

Figure 1: fragment Agnus Dei II uit de Missa L'homme armé super voces musicales as published by Ottaviano Petrucci.

Prolation canon Figure 1 shows a prolation canon from the Missa L'homme armé super voces musicales of Josquin Des Prez. In music, a prolation canon or mensuration canon is a type of canon, a musical composition which employs a melody with one or more imitations of the melody in other voices played after a given duration (e.g. quarter rest, one measure, etc.). In a prolation canon, each voice not only sings or plays the same music, but does so at different speeds (the term prolation refers to these different speeds). The interpretation of the speed is indicated by three special signs at the beginning of the canon (before the first note). Figure 2 shows the opening of the Agnus Dei II from the Missa L'homme armé super voces musicales of Josquin DesPrez. The movement consists of a three-out-of-one mensuration canon. The middle voice is the slowest; the lowest voice sings at twice the speed of the middle voice, and the top voice at three times the speed. The first four notes of the canon are shown connected by lines of the same color. Figure 2: elaboration figur 1