Sometime before 1436 he began to work as a singer at San Marco in Venice, which was then at the very beginning of its rise to fame; the first mention of a choir there is found in a document of 1403 (by the end of the 16th century, it was one of the most renowned musical institutions in Europe).
[1] His musical style is highly varied, and possibly he wrote his surviving pieces over a career of more than the twenty documented years.
According to Giulio Cattin, writing in the New Grove: "Taken as a whole, his output developed in a way typical of the 15th century, from a northern late Gothic idiom to the expressive, tuneful simplicity of Italian music.
Johannes de Quatris: 1436 mensis maij Venet[iis]" – a much-debated notation which may refer to the time and place of composition (May 1436, Venice) or perhaps an occasion for performance, or even the date the manuscript was copied.
The music for the Passion, which includes Lessons for Matins as well as a set of Lamentations, also has been found in a manuscript, now in Vicenza, which was copied around 1440.