Английская Википедия:34 equal temperament

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In musical theory, 34 equal temperament, also referred to as 34-TET, 34-EDO or 34-ET, is the tempered tuning derived by dividing the octave into 34 equal-sized steps (equal frequency ratios). Шаблон:Audio Each step represents a frequency ratio of Шаблон:Radic, or 35.29 cents Шаблон:Audio.

History and use

Unlike divisions of the octave into 19, 31 or 53 steps, which can be considered as being derived from ancient Greek intervals (the greater and lesser diesis and the syntonic comma), division into 34 steps did not arise 'naturally' out of older music theory, although Cyriakus Schneegass proposed a meantone system with 34 divisions based in effect on half a chromatic semitone (the difference between a major third and a minor third, 25:24 or 70.67 cents).Шаблон:Citation needed Wider interest in the tuning was not seen until modern times, when the computer made possible a systematic search of all possible equal temperaments. While Barbour discusses it,[1] the first recognition of its potential importance appears to be in an article published in 1979 by the Dutch theorist Dirk de Klerk.Шаблон:Citation needed The luthier Larry Hanson had an electric guitar refretted from 12 to 34 and persuaded American guitarist Neil Haverstick to take it up.Шаблон:Citation needed

As compared with 31-et, 34-et reduces the combined mistuning from the theoretically ideal just thirds, fifths and sixths from 11.9 to 7.9 cents. Its fifths and sixths are markedly better, and its thirds only slightly further from the theoretical ideal of the 5:4 ratio. Viewed in light of Western diatonic theory, the three extra steps (of 34-et compared to 31-et) in effect widen the intervals between C and D, F and G, and A and B, thus making a distinction between major tones, ratio 9:8 and minor tones, ratio 10:9. This can be regarded either as a resource or as a problem, making modulation in the contemporary Western sense more complex. As the number of divisions of the octave is even, the exact halving of the octave (600 cents) appears, as in 12-et. Unlike 31-et, 34 does not give an approximation to the harmonic seventh, ratio 7:4.

Interval size

The following table outlines some of the intervals of this tuning system and their match to various ratios in the harmonic series.

interval name size (steps) size (cents) midi just ratio just (cents) midi error
octave 34 1200 2:1 1200 0
perfect fifth 20 705.88 Шаблон:Audio 3:2 701.95 Шаблон:Audio +Шаблон:03.93
septendecimal tritone 17 600.00 Шаблон:Audio 17:12 603.00 Шаблон:03.00
lesser septimal tritone 17 600.00 7:5 582.51 Шаблон:Audio +17.49
tridecimal narrow tritone 16 564.71 Шаблон:Audio 18:13 563.38 Шаблон:Audio +Шаблон:01.32
11:8 wide fourth 16 564.71 11:8Шаблон:0 551.32 Шаблон:Audio +13.39
undecimal wide fourth 15 529.41 Шаблон:Audio 15:11 536.95 Шаблон:Audio Шаблон:07.54
perfect fourth 14 494.12 Шаблон:Audio 4:3 498.04 Шаблон:Audio Шаблон:03.93
tridecimal major third 13 458.82 13:10 454.21 Шаблон:Audio +Шаблон:04.61
septimal major third 12 423.53 Шаблон:Audio 9:7 435.08 Шаблон:Audio −11.55
undecimal major third 12 423.53 14:11 417.51 Шаблон:Audio +Шаблон:06.02
major third 11 388.24 Шаблон:Audio 5:4 386.31 Шаблон:Audio +Шаблон:01.92
tridecimal neutral third 10 352.94 Шаблон:Audio 16:13 359.47 Шаблон:Audio Шаблон:06.53
undecimal neutral third 10 352.94 11:9Шаблон:0 347.41 Шаблон:Audio +Шаблон:05.53
minor third Шаблон:09 317.65 Шаблон:Audio 6:5 315.64 Шаблон:Audio +Шаблон:02.01
tridecimal minor third Шаблон:08 282.35 Шаблон:Audio 13:11 289.21 Шаблон:Audio Шаблон:06.86
septimal minor third Шаблон:08 282.35 7:6 266.87 Шаблон:Audio +15.48
tridecimal semimajor second Шаблон:07 247.06 Шаблон:Audio 15:13 247.74 Шаблон:Audio Шаблон:00.68
septimal whole tone Шаблон:07 247.06 8:7 231.17 Шаблон:Audio +15.88
whole tone, major tone Шаблон:06 211.76 Шаблон:Audio 9:8 203.91 Шаблон:Audio +Шаблон:07.85
whole tone, minor tone Шаблон:05 176.47 Шаблон:Audio 10:9Шаблон:0 182.40 Шаблон:Audio Шаблон:05.93
neutral second, greater undecimal Шаблон:05 176.47 11:10 165.00 Шаблон:Audio +11.47
neutral second, lesser undecimal Шаблон:04 141.18 Шаблон:Audio 12:11 150.64 Шаблон:Audio Шаблон:09.46
greater tridecimal Шаблон:2/3-tone Шаблон:04 141.18 13:12 138.57 Шаблон:Audio +Шаблон:02.60
lesser tridecimal Шаблон:2/3-tone Шаблон:04 141.18 14:13 128.30 Шаблон:Audio +12.88
15:14 semitone Шаблон:03 105.88 Шаблон:Audio 15:14 119.44 Шаблон:Audio −13.56
diatonic semitone Шаблон:03 105.88 16:15 111.73 Шаблон:Audio Шаблон:05.85
17th harmonic Шаблон:03 105.88 17:16 104.96 Шаблон:Audio +Шаблон:00.93
21:20 semitone Шаблон:02 Шаблон:070.59 Шаблон:Audio 21:20 Шаблон:084.47 Шаблон:Audio −13.88
chromatic semitone Шаблон:02 Шаблон:070.59 25:24 Шаблон:070.67 Шаблон:Audio Шаблон:00.08
28:27 semitone Шаблон:02 Шаблон:070.59 28:27 Шаблон:062.96 Шаблон:Audio +Шаблон:07.63
septimal sixth-tone Шаблон:01 Шаблон:035.29 Шаблон:Audio 50:49 Шаблон:034.98 Шаблон:Audio +Шаблон:00.31

Scale diagram

The following are 15 of the 34 notes in the scale:

Interval (cents) 106 106 70 35 70 106 106 106 70 35 70 106 106 106
Note name C CШаблон:Music/DШаблон:Music D DШаблон:Music EШаблон:Music E F FШаблон:Music/GШаблон:Music G GШаблон:Music AШаблон:Music A AШаблон:Music/BШаблон:Music B C
Note (cents)   0   106 212 282 318 388 494 600 706 776 812 882 988 1094 1200

The remaining notes can easily be added.

References

Шаблон:Reflist

External links

Шаблон:Microtonal music Шаблон:Musical tuning

  1. Tuning and Temperament, Michigan State College Press, 1951