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 Piano, Violin & Cello: Mozart Divertimento in B-flat major, K.254, Piano & Violin: Rachmaninoff - Vocalise, Piano, Violin & Cello: Dvořák's seventh Humoresque