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 SCHUBERT (2/6): String Quintet in C major - I. Allegro ma no troppo, PENDERECKI Concerto Grosso n°1 pour 3 violoncelles et orchestre, SCHUBERT (1/6): String Quintet in C major - I. Allegro ma no troppo