Figure 3.27
Octatonic I (Oct I) and Octatonic II (Oct II)
Audio 18
Octatonic Scales
Oct I
and
Oct II
have only three forms each.
Figure 3.28 "Octatonic Rotations"
shows
Oct I
with additional re-orderings on successively higher scale degrees. Observe
that, after the original form and two additional transpositions have been listed, the
fourth ordering is equivalent to the first, the fifth is equivalent to the second, and
so forth. The same holds true for
Oct II
.
Figure 3.28
Octatonic Rotations
“Augmented” Scale
Another commonly used hexatonic scale pattern is sometimes called the
“Augmented” scale
27
.This hexachord, along with the Whole Tone, Octatonic, and
Chromatic scales are labeled “Modes of Limited Transposition” in 20th-century
composer Olivier Messiaen’s
Techniques de mon langage musical
. This label refers to
the chords built upon alternate scale degrees. This is also a symmetrical construct,
evenly dividing the octave by the pattern, “half step and a step and a half.” It’s
related counterpart divides the octave by the reverse pattern, “step and a half and
halfstep.”
27. A hexatonic scale that
symmetrically divides the
octave by alternating half step
and step-and-a-half, or the
reverse.
Chapter 3 The Foundations Scale-Steps and Scales
3.5 Other Commonly Used Scales
116