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 Kodaly: String Quartet No. 2 in C minor, Op. 2, Movement III, Presto, Maslanka: Recitation Book, Movement V, Fanfare/Variations on "Durch Adams Fall", Blumer: Quintett for Blasinstrumente, Op. 52, Movement III, Leicht fließend