French composer, who served in John of Gaunt's household in the 1390s. He is one of the most prolific and also most advanced composers represented in the Old Hall MS, and his music reveals a technical virtuosity unique in this period. Three of his Gloria settings are canonic, one being a double canon with a free 5th part; one of his Credos is a complex 3-part canon with two free voices, and an (incomplete) troped Sanctus sets the chant on which it is based as a canon 2 in 1. His style is often very dissonant in the ars nova manner.