“Symphonie Diagonale” (1924) IMDb
Review refers to versions with music by Henrik Frisk, Quartet Twentytwentyone and others, as well as a completetely silent version.
The most famous expression in animation of the 1920s view of cinema as a painterly medium. The visuals are obviously central, but I still recommend some comparatively eventful soundtrack. I find it impossible to recreate, in a modern context, the intended mode of reception.