Misplaced Pages

Delta scale

Article snapshot taken from Wikipedia with creative commons attribution-sharealike license. Give it a read and then ask your questions in the chat. We can research this topic together.
Minor second Play
Chromatic circleThe delta scale's approximations compared with the just valuesTwelve-tone equal temperament vs. just

The δ (delta) scale is a non-octave repeating musical scale. It may be regarded as the beta scale's reciprocal, since it is "as far 'down' the (0 3 6 9) circle from α as β is 'up'". As such it would split the minor second (presumably 16:15) into eight equal parts of approximately 14 cents each Play. This would total approximately 85.7 steps per octave.

The scale step may also precisely be derived from using 50:28 (25:14, 1003.8 cents, A7 upside-down♯, Play) to approximate the interval 3:2⁄5:4, which equals 6:5 (E♭, 315.64 cents, Play). Thus the step is approximately 13.946 cents, and there are 86.049 steps per octave.

50 log 2 ( 3 2 ) + 28 log 2 ( 5 4 ) + 23 log 2 ( 6 5 ) 50 2 + 28 2 + 23 2 = 0.011 621 2701 0.011 621 2701 × 1200 = 13.945 524 1627 {\displaystyle {\begin{aligned}{\frac {50\log _{2}{\left({\frac {3}{2}}\right)}+28\log _{2}{\left({\frac {5}{4}}\right)}+23\log _{2}{\left({\frac {6}{5}}\right)}}{50^{2}+28^{2}+23^{2}}}=0.011\,621\,2701\\0.011\,621\,2701\times 1200=13.945\,524\,1627\end{aligned}}}

(Play)

The Bohlen–Pierce delta scale is based on the tritave and the 7:5:3 "wide" triad (Play) and the 9:7:5 "narrow" triad (Play) (rather than the conventional 4:5:6 triad). Notes include:

1:1 Play
25:21 Play
9:7 Play
75:49 Play
5:3 Play
9:5 Play
15:7 Play
7:3 Play
25:9 Play
3:1 Play
interval name size
(steps)
size
(cents)
just ratio just
(cents)
error
minor third 23 321.23 6:5 315.64 +5.59
major third 28 391.06 5:4 386.31 +4.75
perfect fifth 50 698.32 3:2 701.96 −3.63

See also

References

  1. Taruskin, Richard (1996). Stravinsky and the Russian Traditions: A Biography of the Works through Mavra, p. 1394. ISBN 978-0-520-07099-8.
  2. "What about BP tonality?", The Bohlen-Pierce Site.

Further reading

Microtonal music
Composers Three quarter flat.Three-quarter sharp.
Inventors
Tunings and
scales
Non-octave-
repeating scales
Equal temperament
Just intonation
Concepts and
techniques
Groups and
publications
Compositions
Other topics
Musical tunings
Measurement
Just intonation
Temperaments
Equal
Linear
IrregularWell temperament/Temperament ordinaire (Kirnberger, Vallotti, Werckmeister, Young)
Traditional
non-Western
Non-octave
Musical scales (list)
Main Western
Other types
Ethnic origin
Non-octave
Modes
Modes in Western music
Gregorian
Authentic
Plagal
Other
Diatonic
Jazz minor
Harmonic minor
Harmonic major
Double harmonic scale
Number of tones


Stub icon

This music theory article is a stub. You can help Misplaced Pages by expanding it.

Categories: