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 POPPER PROJECT #35: Joshua Roman plays Etude no. 35 for Cello by David Popper, POPPER PROJECT #27: Joshua Roman plays Etude no. 27 for cello by David Popper (crazy fast!)