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 XCOM Enemy Unknown Soundtrack - Combat Music 5 (Extended) / Michael McCann, UFO Aftershock Soundtrack - Ambient Music 1, UFO Aftershock Soundtrack - Geoscape Music 8