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 Let's Play - Super Mario Bros. 3 (2 Players) - Part 1, Let's Play - Mixed-Up Mother Goose - Part 1, Let's Play - Cyberia Mission Norway - Part 7