Listen to this Rising Tone. Does it sound like an ever ascending scale? Are you sure?

The Risset Scale:

You are actually hearing only one single octave of twelve notes!

Each note of this octave, however, is actually a chord. These chords have an unusual construction that is computer generated.

Each chord is comprised of six individual notes from six different octaves. The notes of each chord have the same pitch -i.e. six C's, six D's - but they are played at six different volumes. This creates ambiguous information for the listener. (See the Discrete page for more information.)

The Risset Scale blends each tone from this special octave into the next tone, over and over again.

This blending, combined with the complex and ambiguous tonal information of each note, creates the illusion of an endlessly rising tone - or of an endlessly descending tone.

The Helix animation illustrates the structure of the Risset Scale.

The six spheres are the six notes that comprise the chords. The spheres line up on the helix because they have the same pitch - C's, D's, E's..... The size of the spheres represents the volume of the notes. You can see that the middle notes in the chords are played the loudest. Each 360° spiral on the helix is equal to one octave. As the scale is played, the spheres glide along the helix to represent the blending of each note - or chord - into the next.

For further Scientific explanations check out our Links page.