4:5:6:7: Difference between revisions

From Xenharmonic Wiki
Jump to navigation Jump to search
TallKite (talk | contribs)
mNo edit summary
m Cleanup
Line 3: Line 3:
'''4:5:6:7''', the ''harmonic seventh chord'', is the simplest [[tetrad]] in [[7-limit]] harmony. It is often used as a tuning target for the [[dominant seventh chord]] in barbershop music (→ [[Wikipedia: Harmonic seventh chord #Barbershop seventh]]), and also for the German augmented sixth chord in [[septimal meantone]].  
'''4:5:6:7''', the ''harmonic seventh chord'', is the simplest [[tetrad]] in [[7-limit]] harmony. It is often used as a tuning target for the [[dominant seventh chord]] in barbershop music (→ [[Wikipedia: Harmonic seventh chord #Barbershop seventh]]), and also for the German augmented sixth chord in [[septimal meantone]].  


It is a [[dyadic chord]] in the [[7-odd-limit]], with its most complex interval a [[7/5]] tritone. It is the [[octave reduction|octave-reduced]] version of the first four odd harmonics, 1:3:5:7, or the first eight harmonics, 1::8. It is the fundamental otonal consonance of the 7-odd-limit. The utonal minor version of this chord is [[70:84:105:120|1–6/5–3/2–12/7]], sometimes called the ''subharmonic sixth chord''. The harmonic seventh chord can be modified by inflecting the [[5/4]] down by [[25/24]] and [[7/4]] down by [[49/48]] to get this chord, or by inflecting both up by [[36/35]] to get the ''subharmonic seventh chord'' [[70:90:105:126|1 - 9/7 - 3/2 - 9/5]].
It is a [[dyadic chord]] in the [[7-odd-limit]], with its most complex interval a [[7/5]] tritone. It is the [[octave reduction|octave-reduced]] version of the first four odd harmonics, 1:3:5:7, or the first eight harmonics, 1::8. It is the fundamental otonal consonance of the 7-odd-limit. The utonal minor version of this chord is [[70:84:105:120|1–6/5–3/2–12/7]], sometimes called the ''subharmonic sixth chord''. The harmonic seventh chord can be modified by inflecting the [[5/4]] down by [[25/24]] and [[7/4]] down by [[49/48]] to get this chord, or by inflecting both up by [[36/35]] to get the ''subharmonic seventh chord'' [[70:90:105:126|1–9/7–3/2–9/5]].


== Audio of close voicings ==
== Audio of close voicings ==
Line 13: Line 13:


== Notable voicings ==
== Notable voicings ==
Sorted by [[Wilson norm#Example|Wilson Height]]. AOV and CAOV stand for [[Odd limit#Proposed extensions|all-odd voicing]] and ''condensed'' AOV respectively. This list is only a brief overview, see [[Voicings of 4:5:6:7]] for a more comprehensive list.
Sorted by [[Wilson norm]]. AOV and CAOV stand for [[Odd limit #Proposed extensions|all-odd voicing]] and ''condensed'' AOV respectively. This list is only a brief overview, see [[Voicings of 4:5:6:7]] for a more comprehensive list.
 
{| class="wikitable"
{| class="wikitable"
|+
|+
!Voices
! Voices
![[EFR]]
! [[EFR]]
![[Kite's thoughts on hi-lo notation|Hi-lo name]]
! [[Kite's thoughts on hi-lo notation|Hi-lo name]]
!Special properties
! Special properties
|-
|-
| rowspan="5" |4 voices
| rowspan="5" |4 voices
|1:3:5:7
| 1:3:5:7
|hi37loR
| hi37loR
|AOV, [[Isodifferential chord|isodifferential]]
| AOV, [[Isodifferential chord|isodifferential]]
|-
|-
|2:3:5:7
| 2:3:5:7
|hi37
| hi37
|CAOV
| CAOV
|-
|-
|3:4:5:7
| 3:4:5:7
|lo5
| lo5
|
|  
|-
|-
|4:5:6:7
| 4:5:6:7
|basic
| Basic
|isodifferential
| Isodifferential
|-
|-
|4:6:7:10
| 4:6:7:10
|hi3
| hi3
|
|  
|}
|}


== Related chords ==
== Related chords ==
Melodic inversion: 7:6:5:4 = [[60:70:84:105]] = 1/1 - 7/6 - 7/5 - 7/4, and its homonym 12:10:8:7 = [[70:84:105:120]] = 1/1 - 6/5 - 3/2 - 12/7.
Melodic inversion: 1/(7:6:5:4) = [[60:70:84:105]] = 1–7/6–7/5–7/4, and its homonym 1/(12:10:8:7) = [[70:84:105:120]] = 1–6/5–3/2–12/7.


Plausible [[Chord homonym|homonyns]]: none.
Plausible [[chord homonym|homonyns]]: none.


Notable extensions (7-limit):
Notable extensions (7-limit):
* [[4:5:6:7:9]] – adds 9/4
* [[4:5:6:7:9]] – adds 9/4
* [[12:15:18:21:28]] – adds 7/3 to make the 7-limit Hendrix chord
* [[12:15:18:21:28]] – adds 7/3 to make the 7-limit Hendrix chord
Notable restrictions:
Notable restrictions:
* [[4:5:6]]
* [[4:5:6]]
* [[4:5:7]]
* [[4:5:7]]

Revision as of 09:38, 24 November 2025

Chord information
Harmonics 4:5:6:7
Subharmonics 1/(105:84:70:60)
Intervals from root 1/15/43/27/4
Cents from root 386¢702¢969¢
Step intervals 5/4, 6/5, 7/6
Step cents 386¢, 316¢, 267¢
Color names yo zo-7 or y,z7
har-7 or h7
Prime limit 7
Genus 357 (105)
Intervallic odd limit 7
Otonal odd limit 7
Utonal odd limit 105
Consistent edos (d ≥ 2) 31edo*, 41edo*, 68edo*, 72edo*
English Wikipedia has an article on:

4:5:6:7, the harmonic seventh chord, is the simplest tetrad in 7-limit harmony. It is often used as a tuning target for the dominant seventh chord in barbershop music (→ Wikipedia: Harmonic seventh chord #Barbershop seventh), and also for the German augmented sixth chord in septimal meantone.

It is a dyadic chord in the 7-odd-limit, with its most complex interval a 7/5 tritone. It is the octave-reduced version of the first four odd harmonics, 1:3:5:7, or the first eight harmonics, 1::8. It is the fundamental otonal consonance of the 7-odd-limit. The utonal minor version of this chord is 1–6/5–3/2–12/7, sometimes called the subharmonic sixth chord. The harmonic seventh chord can be modified by inflecting the 5/4 down by 25/24 and 7/4 down by 49/48 to get this chord, or by inflecting both up by 36/35 to get the subharmonic seventh chord 1–9/7–3/2–9/5.

Audio of close voicings

4:5:6:7, Root position
5:6:7:8, 1st inversion
6:7:8:10, 2nd inversion
7:8:10:12, 3rd inversion

Notable voicings

Sorted by Wilson norm. AOV and CAOV stand for all-odd voicing and condensed AOV respectively. This list is only a brief overview, see Voicings of 4:5:6:7 for a more comprehensive list.

Voices EFR Hi-lo name Special properties
4 voices 1:3:5:7 hi37loR AOV, isodifferential
2:3:5:7 hi37 CAOV
3:4:5:7 lo5
4:5:6:7 Basic Isodifferential
4:6:7:10 hi3

Related chords

Melodic inversion: 1/(7:6:5:4) = 60:70:84:105 = 1–7/6–7/5–7/4, and its homonym 1/(12:10:8:7) = 70:84:105:120 = 1–6/5–3/2–12/7.

Plausible homonyns: none.

Notable extensions (7-limit):

Notable restrictions: