Spaces to Represent Pitch

Play ascending 7ths on the the keyboard; it is possible to hear descending (chromatic) sequence;

A helix on the surface of a cylinder places octaves immediately above and blow each other.

**Figure 6:** A nonlogarithmic pitch helix depicting octave equivalence.
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Shepard tones, ambiguous in height but unambiguous in pitch, can be made to spiral up the helix forever.

Chroma: The position of a note within the octave; chroma circle is the base of the helix.

Pitch height is the vertical position on the helix.

``Music 175: Pitch II'' by Tamara Smyth, Department of Music, University of California, San Diego (UCSD).