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 Bartok: Sonata for two pianos and percussion I, part 2, Quilter Music when soft voices die.m4v, Bartok Sonata for two pianos and percussion: I, part 1