Of all Josquin's polyphonic settings of the Mass Ordinary text, the Missa D'ung aultre amer is the most compact and concise. Not written for any particular festival season, it is one of a very few examples of an "everyday" Mass, suitable for any Sunday during the year. Josquin achieves compactness in part by telescoping the two movements with the longest texts (Gloria and the Credo), often dove-tailing and overlapping phrases of text in different voices; the rapid parlando style of these two movements resembles a kind of harmonized plainchant more than it does the long and graceful melodies usually heard in church music of the early Renaissance.

Josquin provided two unifying elements in his setting. First of all, as the name of the Mass suggests, the five movements are each structured around a complete statement (in the Tenor voice) of a single borrowed melody—in this case "D'ung aultre amer," a French rondeau by Ockeghem. The text of this love song says it would be "impossible to love another," and Josquin adapts this declaration to the sentiment of a devoted worshipper. Secondly, the Kyrie (first movement) and Sanctus both begin with identical duets between the tenor voice and soprano; these duets, which quote the borrowed melody directly (the tune would have been recognized by any courtly audience) provide a measure of motivic unity between the movements, and strengthen the ties to the cantus firmus.

The most unique feature of this Mass occurs in the second half of the Sanctus movement, where Josquin substitutes a personalized devotional motet for the liturgically correct text. Here, the composer's complex polyphony gives way to a simple and affective chordal section, beginning "Tu solus, qui facis mirabilia." The court of Duke Galeazzo Maria Sforza of Milan has been linked to this practice of motet substitution; the fact that Josquin was a singer for the Duke's younger brother during the 1480s suggests the Missa D'ung aultre amer may very well have been written for Milanese use.

© Timothy Dickey, All Music Guide