Английская Википедия:Enharmonic scale

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Шаблон:For

Файл:Enharmonic scale segment on C.png
Enharmonic scale [segment] on C.[1][2] Шаблон:Audio[2] Note that in this depiction CШаблон:Music and DШаблон:Music are distinct rather than equivalent as in modern notation.
Файл:Enharmonic scale on C.png
Enharmonic scale on C.[3]

In music theory, an enharmonic scale is "an [imaginary] gradual progression by quarter tones" or any "[musical] scale proceeding by quarter tones".[3] The enharmonic scale uses dieses (divisions) nonexistent on most keyboards,[2] since modern standard keyboards have only half-tone dieses.

More broadly, an enharmonic scale is a scale in which (using standard notation) there is no exact equivalence between a sharpened note and the flattened note it is enharmonically related to, such as in the quarter tone scale. As an example, FШаблон:Music and GШаблон:Music are equivalent in a chromatic scale (the same sound is spelled differently), but they are different sounds in an enharmonic scale. See: musical tuning.

Musical keyboards which distinguish between enharmonic notes are called by some modern scholars enharmonic keyboards. (The enharmonic genus, a tetrachord with roots in early Greek music, is only loosely related to enharmonic scales.)

Файл:Lesser diesis (difference m2-A1).PNG
Diesis defined in quarter-comma meantone as a diminished second (m2 − A1 ≈ 117.1 − 76.0 ≈ 41.1 cents), or an interval between two enharmonically equivalent notes (from DШаблон:Music to CШаблон:Music). Шаблон:Audio

Consider a scale constructed through Pythagorean tuning. A Pythagorean scale can be constructed "upwards" by wrapping a chain of perfect fifths around an octave, but it can also be constructed "downwards" by wrapping a chain of perfect fourths around the same octave. By juxtaposing these two slightly different scales, it is possible to create an enharmonic scale.

The following Pythagorean scale is enharmonic:

Note Ratio Decimal Cents Difference
(cents)
C Шаблон:01:1 1 Шаблон:00
DШаблон:Music Шаблон:0256:243 1.05350 Шаблон:090.225 23.460
CШаблон:Music Шаблон:02187:2048 1.06787 Шаблон:0113.685
D Шаблон:09:8 1.125 Шаблон:0203.910
EШаблон:Music Шаблон:032:27 1.18519 Шаблон:0294.135 23.460
DШаблон:Music 19683:16384 1.20135 Шаблон:0317.595
E Шаблон:081:64 1.26563 Шаблон:0407.820
F Шаблон:04:3 1.33333 Шаблон:0498.045
GШаблон:Music Шаблон:01024:729 1.40466 Шаблон:0588.270 23.460
FШаблон:Music Шаблон:0729:512 1.42383 Шаблон:0611.730
G Шаблон:03:2 1.5 Шаблон:0701.955
AШаблон:Music Шаблон:0128:81 1.58025 Шаблон:0792.180 23.460
GШаблон:Music Шаблон:06561:4096 1.60181 Шаблон:0815.640
A Шаблон:027:16 1.6875 Шаблон:0905.865
BШаблон:Music Шаблон:016:9 1.77778 Шаблон:0996.090 23.460
AШаблон:Music 59049:32768 1.80203 1019.550
B Шаблон:0243:128 1.89844 1109.775
C′ Шаблон:02:1 2 1200

In the above scale the following pairs of notes are said to be enharmonic:

In this example, natural notes are sharpened by multiplying its frequency ratio by 256:243 (called a limma), and a natural note is flattened by multiplying its ratio by 243:256. A pair of enharmonic notes are separated by a Pythagorean comma, which is equal to 531441:524288 (about 23.46 cents).

References

Шаблон:Reflist

External links

Шаблон:Scales

  1. Шаблон:Cite CEM. Moore cites Greek use of quarter tones until the time of Alexander the Great.
  2. 2,0 2,1 2,2 John Wall Callcott (1833). A Musical Grammar in Four Parts, p.109. James Loring.
  3. 3,0 3,1 Louis Charles Elson (1905). Elson's Music Dictionary, p.100. O. Ditson Company.