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 Go"--Sad Piano Music, Light Jazz, Instrumental Music, "Autumn Love" sad piano music, light Jazz, love music, instrumental music, Sad Music Piano & Violin Sad Love Music (this will make you cry)