The never ending Shepard Scale

When you play the video above over and over again, you will get the sense that the musical scale being heard is ascending forever. In reality, the scale is repeated exactly as it was played the first time. It’s just that our minds get confused because of the way the scale is built.

Scales in music written like the one in the video are known as Shepard Scales (named after Roger Shepard who first discovered it). A Shepard Scale is, in a very basic sense, a bunch of scales played at the same time in different octaves. As the scale moves — up or down — the same notes in each separate octave either fade in or fade out and overlap each other, thus creating the audio “trick” we hear as the never ending scale.

When I first listened to the video above (heh, that’s weird to say) I immediately thought of the never ending stairs in Mario 64 (at the top of the tower in the castle). When you go up the stairs in the game, a similar Shepard Scale is used to reiterate the fact that you are going up a flight of stairs that will never end.

Anyway, neat eh? Now you know the official name of such a scale — the Shepard Scale!