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 Franck-Cortot - Violin Sonata (Piano solo transcription) 4th Movement, Henze - Toccata Mistica (c.1994) (Wagner S. D'A. M. Prado, Piano), Chopin - Nocturne No.14 (Op.48 No.2) in f-sharp minor