The bubbles of Elmo's World, were one of the creative scene transitions. Mostly scene after the Mr. Noodle segments. It has colorful outlines and a flute and a clarinet playing the C Major scale. There are currently 2 versions of the sounds. version one for example, is on Babies, Dogs. Version 2 is Bugs, Farm, and the Wild Wild West special. It creeped me out half to death when I was little