Symmetrical Scale Patterns
Composers in this historically transitional period and throughout the 20th Century
seemed fascinated by aspects of symmetry in musical constructs.The symmetrical
nature of the Pentatonic scale is not overtly obvious. The symmetry is there, but its
explanation must be held in abeyance contingent upon other acquired information.
In scale construction, this took the form of division of the octave into symmetrical
portions. This is apparent in the types of scale patterns that came into common use
in the late 19th Century and continued throughout the 20th Century.
Whole Tone Scale
The
Whole Tone Scale
25
, properly considered to be a Hexatonic (six-tone) scale,
displays numerous symmetrical traits.There are numerous “axes of symmetry” in
whole tone scales. Only those pertinent to this discussion are included here. It is
comprised of all whole steps, dividing the octave symmetrically into six portions of
two half steps each.
Figure 3.24
The Whole Tone Scale
Since this symmetrical division accounts for six of the possible twelve pitch-classes
from the chromatic collection, the other six pitch-classes of the chromatic
collection form one other whole tone scale.
Figure 3.25
Whole Tone I (WT I) and Whole Tone II (WT II)
Audio 16
Whole Tone Scales
25. A hexatonic scale comprised of
only whole steps that divides
the octave symmetrically into
six equal portions of two half
steps each.
Chapter 3 The Foundations Scale-Steps and Scales
3.5 Other Commonly Used Scales
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