source of light is a neutral, low-energy track by Opt from 夜、寝る前に聴く音楽集, released March 15, 2015. It runs 1:36 at 68 テンポ (136 テンポ double-time) in C Major (Camelot 8B).
Find the テンポ and music key for any song with our テンポ and キー Finder.