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 Rhys Meilyr (11 year-old Boy treble) singing Pie Jesu.wmv, Aled Jones Boy soprano singing Ave Maria (Bach-Gounod), Aled Jones (boy treble) singing Star of Bethlehem.wmv