User:Dummy index/Semitritave: Difference between revisions

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==False octave==
==False octave==
Semitritave is available for [[Ed5/3 through ed7/3|false octave]]. Differ from [[acoustic phi]] or [[ed7/4]], two equave makes [[3/1|3:1]], well-known equave.
Semitritave is available for [[Ed5/3 through ed7/3|false octave]]. Differ from [[acoustic phi]] or [[ed7/4]], two equave makes 3:1, well-known equave.


==2*N-edt==
==2*N-edt==
Every even-numbered [[EDT]] has semitritave interval. Treating it as equave. Another preferrable intervals...
Every even-numbered EDT has semitritave interval. Treating it as equave. Another preferable intervals...


* 5edt - 380 cents major third
* 5edt - 380 cents major third
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* so 30edt?
* so 30edt?


To do mechanical translation from diatonic scores, "fifth" sound is preferred to be consonance. 7/5 is better, but it makes [[3L 2s]]. 11/8 corresponds meantone region. (for this purpose, [[ed9/5]] is good answer.)
To do mechanical translation from diatonic scores, "fifth" sound is preferred to be consonance. 7/5 is better, but it makes [[3L 2s]]. 11/8 corresponds to meantone region. (for this purpose, [[ed9/5]] is good choice.)


* 24edt - simple. "Fifth" is "7\12" ≈ 11/8, off by 3 cents.
* 24edt - simple. "Fifth" is "7\12" ≈ 11/8, off by 3 cents.
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* 38edt - approximately 24edo. "Fifth" is "11\19" ≈ 11/8. Can convert easily from 19edo.
* 38edt - approximately 24edo. "Fifth" is "11\19" ≈ 11/8. Can convert easily from 19edo.
* 36edt - approximately [[23edo and octave stretching|stretched 23edo]]. Another candidate with "fifth" 7/5...
* 36edt - approximately [[23edo and octave stretching|stretched 23edo]]. Another candidate with "fifth" 7/5...
* 54edt - approximately 34edo. Two "fifth," "16\27" ≈ 18/13 and "15\27" ≈ 19/14 are precise. Together with "9\27" ≈ 6/5 and "11\27" ≈ 5/4, seems to good for micro- augene<nowiki>[12]</nowiki>.
* 54edt - approximately 34edo. Two "fifth," "16\27" ≈ 18/13 and "15\27" ≈ 19/14 are precise. Together with "9\27" ≈ 6/5 and "11\27" ≈ 5/4, seems good for micro- augene<nowiki>[12]</nowiki>.
* 62edt - approximately 39edo. "Fifth" is "18\31" ≈ 11/8, and "wolf fifth" is "19\31" ≈ 7/5.
 
==Memo==
[http://x31eq.com/cgi-bin/pregular.cgi?limit=3.5%2F2.11%2F8&error=5.0 3.5/2.11/8 => 24edt],
[http://x31eq.com/cgi-bin/pregular.cgi?limit=3.5%2F2.7%2F2&error=5.0 3.5/2.7/2 => 36edt],
[http://x31eq.com/cgi-bin/pregular.cgi?limit=3.2.11.17&error=5.0 3.2.11.17 => 38edt],
[http://x31eq.com/cgi-bin/pregular.cgi?limit=3.2.11%2F5.13%2F5&error=5.0 3.2.11/5.13/5 => 46edt],
[http://x31eq.com/cgi-bin/pregular.cgi?limit=3.2.5.11.13&error=5.0 3.2.5.13.17 => 54edt],
[http://x31eq.com/cgi-bin/pregular.cgi?limit=3.10.14.17.23&error=5.0 3.10.14.17.23 => 62edt]

Revision as of 14:28, 16 February 2022

Interval information
Expression [math]\displaystyle{ (3/1)^(1/2) }[/math]
Monzo [0 1/2
Size in cents 950.9775¢
Name semitritave
Special properties reduced

Interval

Semitritave, square root of 3:1, is an interseptimal interval. It divide pure tritave into two equal parts. Every even-numbered EDT has this interval.

Merciful intonation

Semitritave is an candidate for "practically merciful intonation", because it is [math]\displaystyle{ [1; 1, 2, 1, 2, ...] }[/math] in continued fraction, have many gradually proximal ratios, 5/3, 7/4, 19/11, 26/15, 71/41, ..., makes rich dissonance.

Approximating it by noble number:

  • [math]\displaystyle{ [1; 1, 2, 1, 1, 1, ...] }[/math] - 942.5 cents, between 12/7 and 19/11.
  • [math]\displaystyle{ [1; 1, 2, 1, 2, 1, 1, 1, ...] }[/math] - 950.4 cents, between 45/26 and 71/41.
  • [math]\displaystyle{ [1; 1, 2, 1, 3, 1, 1, 1, ...] }[/math] - 954.6 cents, between 26/15 and 33/19.

False octave

Semitritave is available for false octave. Differ from acoustic phi or ed7/4, two equave makes 3:1, well-known equave.

2*N-edt

Every even-numbered EDT has semitritave interval. Treating it as equave. Another preferable intervals...

  • 5edt - 380 cents major third
  • 6edt - 317 cents minor third
  • so 30edt?

To do mechanical translation from diatonic scores, "fifth" sound is preferred to be consonance. 7/5 is better, but it makes 3L 2s. 11/8 corresponds to meantone region. (for this purpose, ed9/5 is good choice.)

  • 24edt - simple. "Fifth" is "7\12" ≈ 11/8, off by 3 cents.
  • 46edt - approximately 29edo. This have two "fifth," "14\23" ≈ 7/5, "13\23" ≈ 15/11.
  • 38edt - approximately 24edo. "Fifth" is "11\19" ≈ 11/8. Can convert easily from 19edo.
  • 36edt - approximately stretched 23edo. Another candidate with "fifth" 7/5...
  • 54edt - approximately 34edo. Two "fifth," "16\27" ≈ 18/13 and "15\27" ≈ 19/14 are precise. Together with "9\27" ≈ 6/5 and "11\27" ≈ 5/4, seems good for micro- augene[12].
  • 62edt - approximately 39edo. "Fifth" is "18\31" ≈ 11/8, and "wolf fifth" is "19\31" ≈ 7/5.

Memo

3.5/2.11/8 => 24edt, 3.5/2.7/2 => 36edt, 3.2.11.17 => 38edt, 3.2.11/5.13/5 => 46edt, 3.2.5.13.17 => 54edt, 3.10.14.17.23 => 62edt