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 Breaking a mallet :D White Knuckle Stroll by C.Cangelosi played by Miroslav Dimov, Worlds Away by E.Gorcheva/M. Dimov - Concerto for marimba, percussions, piano and string orchestra, Bulgarian bouquet by Trakia percussion group