Ko-Ko Song Car-Tunes, Song Car-Tunes, or (some sources erroneously say) Sound Car-Tunes, is a series of short three-minute animated films produced by Max Fleischer and Dave Fleischer between May 1924 and September 1927, pioneering the use of the "Follow the Bouncing Ball" device used to lead audiences in theater sing-alongs. The Song Car-Tunes also pioneered the application of sound film to animation.