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 Choir of the Sound: African Noel (December 1998), Choir of the Sound: Break Forth, O Beauteous Heavenly Light, Choir of the Sound: It's the Most Wonderful Time of the Year