Kestrel chords: Difference between revisions

From Xenharmonic Wiki
Jump to navigation Jump to search
m Recategorize
Xenllium (talk | contribs)
Update the article
Line 1: Line 1:
The ''[[kestrel]] [[tetrad]]'' is the [[13-limit]], [[Dyadic chord|essentially tempered tetrad]] consisting, in close position, of the steps 13/11-7/6-13/11-11/9 in a [[temperament]] tempering out the kestrel comma, [[1188/1183]], leading to the tempering of 1-13/11-18/13-18/11. Contained in the kestrel tetrad are the two [[Kestrel triad|kestrel triads]], 1-7/6-18/13 and 1-13/11-18/13.  
'''Kestrel chords''' are [[Dyadic chord|essentially tempered chords]] tempered by the kestrel comma, [[1188/1183]].


Closely related tetrads require the tempering of both 1188/1183 and [[540/539]], with steps of 7/6-13/11-13/11-11/9, leading to the tempered version of 1-7/6-18/13-18/11, and 11/9-13/11-13/11-7/6, leading to the 1-11/9-13/9-12/7 chord. [[EDO|Equal temperaments]] tempering out both 1188/1183 and 540/539 include [[41edo|41]], [[53edo|53]], [[58edo|58]], [[94edo|94]], [[103edo|103]], [[111edo|111]], [[161edo|161]], [[205edo|205]], [[214edo|214]], [[255edo|255]].  
Kestrel chords are of [[Dyadic chord/Pattern of essentially tempered chords|pattern 2]] in the 2.3.7.11.13 subgroup [[13-odd-limit]], meaning that there are 6 triads, 15 tetrads and 6 pentads, for a total of 27 distinct chord structures.


255edo is the [[optimal patent val]] for both {1188/1183, 540/539}-tempering and 1188/1183-tempering, so nothing significant is lost in tuning accuracy by also tempering out 540/539. Kestrel tetrads are essentially tempered tetrads of the 2.7/3.11/9.13/9 [[just intonation subgroup]].
For triads, there are three pairs of chords in inverse relationship:
* 1-7/6-18/13 with steps of 7/6-13/11-13/9, and its inverse
* 1-13/11-18/13 with steps of 13/11-7/6-13/9;
* 1-14/11-18/13 with steps of 14/11-13/12-13/9, and its inverse
* 1-13/12-18/13 with steps of 13/12-14/11-13/9;
* 1-13/11-9/7 with steps of 13/11-13/12-14/9, and its inverse
* 1-13/12-9/7 with steps of 13/12-13/11-14/9.
 
For tetrads, there are three palindromic chords and six pairs of chords in inverse relationship. The palindromic chords are
* 1-13/11-18/13-18/11 with steps of 13/11-7/6-13/11-11/9;
* 1-13/12-18/13-3/2 with steps of 13/12-14/11-13/12-4/3;
* 1-13/12-13/11-9/7 with steps of 13/12-12/11-13/12-14/9.
 
The inversely related pairs of chords are
* 1-11/9-13/9-11/7 with steps of 11/9-13/11-13/12-14/11, and its inverse
* 1-13/12-9/7-11/7 with steps of 13/12-13/11-11/9-14/11;
* 1-7/6-18/13-3/2 with steps of 7/6-13/11-13/12-4/3, and its inverse
* 1-13/12-9/7-3/2 with steps of 13/12-13/11-7/6-4/3;
* 1-13/11-9/7-18/13 with steps of 13/11-13/12-14/13-13/9, and its inverse
* 1-14/13-7/6-18/13 with steps of 14/13-13/12-13/11-13/9;
* 1-13/11-14/11-18/13 with steps of 13/11-14/13-13/12-13/9, and its inverse
* 1-13/12-7/6-18/13 with steps of 13/12-14/13-13/11-13/9;
* 1-7/6-14/11-18/13 with steps of 7/6-12/11-13/12-13/9, and its inverse
* 1-13/12-13/11-18/13 with steps of 13/12-12/11-7/6-13/9;
* 1-13/12-9/7-18/13 with steps of 13/12-13/11-14/13-13/9, and its inverse
* 1-14/13-14/11-18/13 with steps of 14/13-13/11-13/12-13/9.
 
For pentads, there are three pairs of chords in inverse relationship:
* 1-13/11-9/7-18/13-18/11 with steps of 13/11-13/12-14/13-13/11-11/9, and its inverse
* 1-13/11-14/11-18/13-18/11 with steps of 13/11-14/13-13/12-13/11-11/9;
* 1-13/12-7/6-18/13-3/2 with steps of 13/12-14/13-13/11-13/12-4/3, and its inverse
* 1-13/12-9/7-18/13-3/2 with steps of 13/12-13/11-14/13-13/12-4/3;
* 1-13/12-13/11-9/7-18/13 with steps of 13/12-12/11-13/12-14/13-13/9, and its inverse
* 1-14/13-7/6-14/11-18/13 with steps of 14/13-13/12-12/11-13/12-13/9.
 
Equal temperaments with kestrel chords include {{Optimal ET sequence|17, 24, 26, 41, 53, 58, 77, 94, 103, 111, 161, 205, 214 and 255}}, with 255edo giving the [[optimal patent val]].


[[Category:13-odd-limit]]
[[Category:13-odd-limit]]
Line 9: Line 44:
[[Category:Triads]]
[[Category:Triads]]
[[Category:Tetrads]]
[[Category:Tetrads]]
[[Category:Pentads]]
[[Category:Kestrel]]
[[Category:Kestrel]]

Revision as of 13:48, 3 November 2023

Kestrel chords are essentially tempered chords tempered by the kestrel comma, 1188/1183.

Kestrel chords are of pattern 2 in the 2.3.7.11.13 subgroup 13-odd-limit, meaning that there are 6 triads, 15 tetrads and 6 pentads, for a total of 27 distinct chord structures.

For triads, there are three pairs of chords in inverse relationship:

  • 1-7/6-18/13 with steps of 7/6-13/11-13/9, and its inverse
  • 1-13/11-18/13 with steps of 13/11-7/6-13/9;
  • 1-14/11-18/13 with steps of 14/11-13/12-13/9, and its inverse
  • 1-13/12-18/13 with steps of 13/12-14/11-13/9;
  • 1-13/11-9/7 with steps of 13/11-13/12-14/9, and its inverse
  • 1-13/12-9/7 with steps of 13/12-13/11-14/9.

For tetrads, there are three palindromic chords and six pairs of chords in inverse relationship. The palindromic chords are

  • 1-13/11-18/13-18/11 with steps of 13/11-7/6-13/11-11/9;
  • 1-13/12-18/13-3/2 with steps of 13/12-14/11-13/12-4/3;
  • 1-13/12-13/11-9/7 with steps of 13/12-12/11-13/12-14/9.

The inversely related pairs of chords are

  • 1-11/9-13/9-11/7 with steps of 11/9-13/11-13/12-14/11, and its inverse
  • 1-13/12-9/7-11/7 with steps of 13/12-13/11-11/9-14/11;
  • 1-7/6-18/13-3/2 with steps of 7/6-13/11-13/12-4/3, and its inverse
  • 1-13/12-9/7-3/2 with steps of 13/12-13/11-7/6-4/3;
  • 1-13/11-9/7-18/13 with steps of 13/11-13/12-14/13-13/9, and its inverse
  • 1-14/13-7/6-18/13 with steps of 14/13-13/12-13/11-13/9;
  • 1-13/11-14/11-18/13 with steps of 13/11-14/13-13/12-13/9, and its inverse
  • 1-13/12-7/6-18/13 with steps of 13/12-14/13-13/11-13/9;
  • 1-7/6-14/11-18/13 with steps of 7/6-12/11-13/12-13/9, and its inverse
  • 1-13/12-13/11-18/13 with steps of 13/12-12/11-7/6-13/9;
  • 1-13/12-9/7-18/13 with steps of 13/12-13/11-14/13-13/9, and its inverse
  • 1-14/13-14/11-18/13 with steps of 14/13-13/11-13/12-13/9.

For pentads, there are three pairs of chords in inverse relationship:

  • 1-13/11-9/7-18/13-18/11 with steps of 13/11-13/12-14/13-13/11-11/9, and its inverse
  • 1-13/11-14/11-18/13-18/11 with steps of 13/11-14/13-13/12-13/11-11/9;
  • 1-13/12-7/6-18/13-3/2 with steps of 13/12-14/13-13/11-13/12-4/3, and its inverse
  • 1-13/12-9/7-18/13-3/2 with steps of 13/12-13/11-14/13-13/12-4/3;
  • 1-13/12-13/11-9/7-18/13 with steps of 13/12-12/11-13/12-14/13-13/9, and its inverse
  • 1-14/13-7/6-14/11-18/13 with steps of 14/13-13/12-12/11-13/12-13/9.

Equal temperaments with kestrel chords include 17, 24, 26, 41, 53, 58, 77, 94, 103, 111, 161, 205, 214 and 255, with 255edo giving the optimal patent val.