videos in AudioSet
A list of about a million ten-second YouTube clips, each labelled with the sounds in it, that Google published in 2017. Labs use it to train and test general audio and music models.
Including Sanctus XI from Mass XI, Gregorian Chant (Brébeuf Hymnal), Agnus Dei III from Mass III, Gregorian Chant, Agnus VI from Mass VI, Gregorian Chant