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 Royalty Free Background Music - "The Payback" (Background Music for Films) (Easy Music Licensing), Royalty Free Background Music - "A Story Unfolds" (Background Music for Films), Royalty Free Background Music - "Internal Sequence" (Background Music for Trailers & Films)