- 1 5 Equal Divisions of the Octave: Theory
- 2 5-edo in Musicmaking
5 Equal Divisions of the Octave: Theory
There is a lot of near-equipentatonic world music, just google "gyil" or "amadinda" or "slendro".
Listen to the sound of the 5-edo scale
For any musician, there is no substitute for the experience of a particular xenharmonic sound. The user going by the name Hyacinth on Wikipedia and Wikimedia Commons has many xenharmonic MIDI's and has graciously copylefted them! This is his 5-edo scale MIDI:
Intervals in 5-edo
|The "neighborhood" of just intervals|
|0||0||unison / prime||exactly 1/1|
|1||240||second, third||+8.826¢ from septimal second 8/7
-4.969¢ from diminished third 144/125
-13.076¢ from augmented second 125/108
-26.871¢ from septimal minor third 7/6
|2||480||fourth||+9.219¢ from narrow fourth 21/16
-0.686¢ from smaller fourth 33/25
-18.045¢ from just fourth 4/3
|3||720||fifth||+18.045¢ from just fifth 3/2
+0.686¢ from bigger fifth 50/33
-9.219¢ from wide fifth 32/21
|4||960||sixth, seventh||26.871¢ from septimal major sixth 12/7
13.076¢ from diminished seventh 216/125
4.969¢ from augmented sixth 125/72
-8.826¢ from septimal seventh 7/4
|5||1200||octave / eighth||exactly 2/1|
- By its cardinality, 5-edo is related to other pentatonic scales, and it is especially close in sound to many Indonesian slendros.
- Due to the interest around the "fifth" interval size, there are many nonoctave "stretch sisters" to 5-edo: square root of 4/3, cube root of 3/2, 8th root of 3, etc.
- For the same reason there are many "circle sisters":
- Make a chain of five "bigger fifths" (50/33), which makes three octaves 3.227¢ flat. (50/33)^5=7.985099.
As a temperament
If 5-edo is regarded as a temperament, which is to say as 5-et, then the most salient fact is that 16/15 is tempered out. This means in 5-et the major third and the fourth, and the minor sixth and the fifth, are not distinguished; this is 5-limit father temperament.
Also tempered out is 27/25, if we temper this out in preference to 16/15 we obtain bug temperament, which equates 10/9 with 6/5: it is a little more perverse even than father. Because these intervals are so large, this sort of analysis is less significant with 5 than it becomes with larger and more accurate divisions, but it still plays a role. For example, I-IV-V-I is the same as I-III-V-I and involves triads with common intervals because of fourth-thirds equivalence.
Despite its lack of accuracy, 5EDO is the second zeta integral edo, after 2EDO. It also is the smallest equal division representing the 9-limit consistently, giving a distinct value modulo five to 2, 3, 5, 7 and 9. Hence in a way similar to how 4edo can be used, and which is discussed in that article, it can be used to represent 7-limit intervals in terms of their position in a pentad, by giving a triple of integers representing a pentad in the lattice of tetrads/pentads together with the number of scale steps in 5EDO. However, while 2edo represents the 3-limit consistently, 3edo the 5-limit, 4edo the 7-limit and 5edo the 9-limit, to represent the 11-limit consistently with a patent val requires going all the way to 22edo.
5 is a prime number so 5-edo contains no sub-edos. Only simple cycles:
- Cycle of seconds: 0-1-2-3-4-0
- Cycle of fourths: 0-2-4-1-3-0
- Cycle of fifths: 0-3-1-4-2-0
- Cycle of sevenths: 0-4-3-2-1-0
5-edo in Musicmaking
- Herman Miller: Daybreak on Slendro Mountain (2000)
- Aaron K. Johnson: 5tet funk (2004)
- Andrew Heathwaite: //Pinta Penta// (2004) play (rendered in 6 alternative pentatonics as well)
- Hans Straub: Asîmchômsaia play
- Brian Wong: Slendronica#1b play
- Brian McLaren: various and sundry
- Paul Rubenstein: various, with electric guitars in 10- and 15-edo
- X.J.Scott: Sleeping Through It All (2004)
- Bill Sethares: 5-tet funk (2004), Pentacle (2004)
- "Cenobyte" Ukulele http://www.youtube.com/watch?v=UKUCRnEJKKU
- "True Island" (album) by Small Scale Revolution (2011)
- Ralph Jarzombek: Micro12
There is a lot of 5edo world music, search for "gyil" or "amadinda" or "slendro".
5edo ear-training exercises by Alex Ness available here.
- via Reinhard's cents notation
- naturals on a five-line staff, with enharmonics (used interchangably) E=F and B=C
- a four-line hybrid treble/bass staff.
5edo does not have any strong consonance nor dissonance. The 240 cent interval can serve as either a major second or minor third, and the 960 cent interval as either a major sixth or minor seventh. The fourth is about 18 cents flat of a just fourth, making it rather "dirty" but recognizable. The fifth is likewise about 18 cents sharp of a just fifth, dissonant but still easily recognizable.
In contrast to other EDOs, all of the notes can be used at once in order to get a functioning scale. (As in Blackwood in 10-EDO).
Smallest EDO that can be used for melodies in a "standard" way. The relatively large step of 240 cents can be used as major second for the melody construction. The scale has whole-tone as well as pentatonic character.
Chord or scale?
Either way, it is hard to wander very far from where you start. However, it has the scale-like feature that there are (barely) enough notes to create melody, in the form of an equal version of pentatonic.
5-EDO tempers out the following commas. (Note: This assumes the val < 5 8 12 14 17 19 |.)
|Comma||Value (cents)||Name||Second Name||Third Name||Monzo|
|256/243||90.225||Limma||Pythagorean Minor 2nd||| 8 -5 >|
|81/80||21.506||Syntonic Comma||Didymos Comma||Meantone Comma||| -4 4 -1 >|
|2889416/2882415||4.200||Vulture||| 24 -21 4 >|
|36/35||48.770||Septimal Quarter Tone||| 2 2 -1 -1 >|
|49/48||35.697||Slendro Diesis||| -4 -1 0 2 >|
|64/63||27.264||Septimal Comma||Archytas' Comma||Leipziger Komma||| 6 -2 0 -1 >|
|245/243||14.191||Sensamagic||| 0 -5 1 2 >|
|1728/1715||13.074||Orwellisma||Orwell Comma||| 6 3 -1 -3 >|
|1029/1024||8.433||Gamelisma||| -10 1 0 3 >|
|19683/19600||7.316||Cataharry||| -4 9 -2 -2 >|
|5120/5103||5.758||Hemifamity||| 10 -6 1 -1 >|
|1065875/1063543||3.792||Wadisma||| -26 -1 1 9 >|
|420175/419904||1.117||Wizma||| -6 -8 2 5 >|
|99/98||17.576||Mothwellsma||| -1 2 0 -2 1 >|
|896/891||9.688||Pentacircle||| 7 -4 0 1 -1 >|
|385/384||4.503||Keenanisma||| -7 -1 1 1 1 >|
|441/440||3.930||Werckisma||| -3 2 -1 2 -1 >|
|3025/3024||0.572||Lehmerisma||| -4 -3 2 -1 2 >|
|91/90||19.130||Superleap||| -1 -2 -1 1 0 1 >|
|676/675||2.563||Parizeksma||| 2 -3 -2 0 0 2 >|
|16/15||111.731||Diatonic semitone||| 4 -1 -1 >|
|14/13||128.298||| 1 0 0 1 0 -1 >|
|27/25||133.238||Large diatonic semit.||| 0 3 -2 >|
|11/10||165.004||Large neutral second||| -1 0 -1 0 1 >|