French composer. probably came to Italy between 1513 and 1515, and worked for Sigismondo d'Este at Ferrara in 1517, In 1524 he moved to Mantua, joining Bishop Ercole Gonzaga's chapel in 1526 and becoming maestro di cappellaat Mantua cathedral from 1539. He should not be confused with Jachet Berchem. He wrote many volumes of church music, including a joint publication with Willaert of Vespers psalms for double choir (1550).