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 Rued Langgaard: Symphony #13 "Belief in Wonders", BVN 319, Myaskovsky: Symphony #15 in D Minor, Op. 38 - I Andante. Allegro apassionato, Beethoven: Violin Sonata #1 in D Major, Op. 12 #1 - III Rondo (Allegro)