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 Classical Music - String Quintet - "La Strada A Damasco" in E-Flat Major ...or "Hidden Canon", Classical Music: The Ascension: Opus One, The Wildhorse Symphony Orchestra w/ The Dream Choir (RSDR)