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Scale 3813: "Aeologyllic"

Bracelet Diagram

The bracelet shows tones that are in this scale, starting from the top (12 o'clock), going clockwise in ascending semitones. The "i" icon marks imperfect tones that do not have a tone a fifth above. Dotted lines indicate axes of symmetry.

Tonnetz Diagram

Tonnetz diagrams are popular in Neo-Riemannian theory. Notes are arranged in a lattice where perfect 5th intervals are from left to right, major third are northeast, and major 6th intervals are northwest. Other directions are inverse of their opposite. This diagram helps to visualize common triads (they're triangles) and circle-of-fifth relationships (horizontal lines).

Common Names

Zeitler: Aeologyllic

Dozenal: YENian

Analysis

Cardinality Cardinality is the count of how many pitches are in the scale.	8 (octatonic)
Pitch Class Set The tones in this scale, expressed as numbers from 0 to 11	{0,2,5,6,7,9,10,11}
Forte Number A code assigned by theorist Allen Forte, for this pitch class set and all of its transpositional (rotation) and inversional (reflection) transformations.	8-14
Rotational Symmetry Some scales have rotational symmetry, sometimes known as "limited transposition". If there are any rotational symmetries, these are the intervals of periodicity.	none
Reflection Axes If a scale has an axis of reflective symmetry, then it can transform into itself by inversion. It also implies that the scale has Ridge Tones. Notably an axis of reflection can occur directly on a tone or half way between two tones.	none
Palindromicity A palindromic scale has the same pattern of intervals both ascending and descending.	no
Chirality A chiral scale can not be transformed into its inverse by rotation. If a scale is chiral, then it has an enantiomorph.	yes enantiomorph: 1263
Hemitonia A hemitone is two tones separated by a semitone interval. Hemitonia describes how many such hemitones exist.	5 (multihemitonic)
Cohemitonia A cohemitone is an instance of two adjacent hemitones. Cohemitonia describes how many such cohemitones exist.	3 (tricohemitonic)
Imperfections An imperfection is a tone which does not have a perfect fifth above it in the scale. This value is the quantity of imperfections in this scale.	2
Modes Modes are the rotational transformations of this scale. This number includes the scale itself, so the number is usually the same as its cardinality; unless there are rotational symmetries then there are fewer modes.	8
Prime Form Describes if this scale is in prime form, using the Starr/Rahn algorithm.	no prime: 759
Generator Indicates if the scale can be constructed using a generator, and an origin.	none
Deep Scale A deep scale is one where the interval vector has 6 different digits, an indicator of maximum hierarchization.	no
Interval Structure Defines the scale as the sequence of intervals between one tone and the next.	[2, 3, 1, 1, 2, 1, 1, 1]
Interval Vector Describes the intervallic content of the scale, read from left to right as the number of occurences of each interval size from semitone, up to six semitones.	<5, 5, 5, 5, 6, 2>
Proportional Saturation Vector First described by Michael Buchler (2001), this is a vector showing the prominence of intervals relative to the maximum and minimum possible for the scale's cardinality. A saturation of 0 means the interval is present minimally, a saturation of 1 means it is the maximum possible.	<0.333, 0.333, 0.25, 0.333, 0.667, 0>
Interval Spectrum The same as the Interval Vector, but expressed in a syntax used by Howard Hanson.	p⁶m⁵n⁵s⁵d⁵t²
Distribution Spectra Describes the specific interval sizes that exist for each generic interval size. Each generic <g> has a spectrum {n,...}. The Spectrum Width is the difference between the highest and lowest values in each spectrum.	<1> = {1,2,3} <2> = {2,3,4,5} <3> = {3,4,5,6} <4> = {5,7} <5> = {6,7,8,9} <6> = {7,8,9,10} <7> = {9,10,11}
Spectra Variation Determined by the Distribution Spectra; this is the sum of all spectrum widths divided by the scale cardinality.	2.25
Maximally Even A scale is maximally even if the tones are optimally spaced apart from each other.	no
Maximal Area Set A scale is a maximal area set if a polygon described by vertices dodecimetrically placed around a circle produces the maximal interior area for scales of the same cardinality. All maximally even sets have maximal area, but not all maximal area sets are maximally even.	no
Interior Area Area of the polygon described by vertices placed for each tone of the scale dodecimetrically around a unit circle, ie a circle with radius of 1.	2.616
Polygon Perimeter Perimeter of the polygon described by vertices placed for each tone of the scale dodecimetrically around a unit circle.	6.002
Myhill Property A scale has Myhill Property if the Distribution Spectra have exactly two specific intervals for every generic interval.	no
Centre of Gravity Distance When tones of a scale are imagined as physical objects of equal weight arranged around a unit circle, this is the distance from the center of the circle to the center of gravity for all the tones. A perfectly balanced scale has a CoG distance of zero.	0.188246
Ridge Tones Ridge Tones are those that appear in all transpositions of a scale upon the members of that scale. Ridge Tones correspond directly with axes of reflective symmetry.	none
Propriety Also known as Rothenberg Propriety, named after its inventor. Propriety describes whether every specific interval is uniquely mapped to a generic interval. A scale is either "Proper", "Strictly Proper", or "Improper".	Improper
Heteromorphic Profile Defined by Norman Carey (2002), the heteromorphic profile is an ordered triple of (c, a, d) where c is the number of contradictions, a is the number of ambiguities, and d is the number of differences. When c is zero, the scale is Proper. When a is also zero, the scale is Strictly Proper.	(34, 56, 136)
Coherence Quotient The Coherence Quotient is a score between 0 and 1, indicating the proportion of coherence failures (ambiguity or contradiction) in the scale, against the maximum possible for a cardinality. A high coherence quotient indicates a less complex scale, whereas a quotient of 0 indicates a maximally complex scale.	0.662
Sameness Quotient The Sameness Quotient is a score between 0 and 1, indicating the proportion of differences in the heteromorphic profile, against the maximum possible for a cardinality. A higher quotient indicates a less complex scale, whereas a quotient of 0 indicates a scale with maximum complexity.	0.306

Generator

This scale has no generator.

Common Triads

These are the common triads (major, minor, augmented and diminished) that you can create from members of this scale.

* Pitches are shown with C as the root

Triad Type	Triad^*	Pitch Classes	Degree	Eccentricity	Closeness Centrality
Major Triads	D	{2,6,9}	3	3	1.7
	F	{5,9,0}	2	5	2.5
	G	{7,11,2}	2	5	2.5
	A♯	{10,2,5}	3	3	1.7
Minor Triads	dm	{2,5,9}	3	4	1.9
	gm	{7,10,2}	2	4	2.1
	bm	{11,2,6}	3	4	1.9
Augmented Triads	D+	{2,6,10}	4	3	1.5
Diminished Triads	f♯°	{6,9,0}	2	4	2.3
Diminished Triads	b°	{11,2,5}	2	4	2.1

view full size

Above is a graph showing opportunities for parsimonious voice leading between triads^*. Each line connects two triads that have two common tones, while the third tone changes by one generic scale step.

Diameter	5
Radius	3
Self-Centered	no
Central Vertices	D, D+, A♯
Peripheral Vertices	F, G

Modes

Modes are the rotational transformation of this scale. Scale 3813 can be rotated to make 7 other scales. The 1st mode is itself.

2nd mode: Scale 1977	Dagyllic
3rd mode: Scale 759	Katalyllic	This is the prime mode
4th mode: Scale 2427	Katoryllic
5th mode: Scale 3261	Dodyllic
6th mode: Scale 1839	Zogyllic
7th mode: Scale 2967	Madyllic
8th mode: Scale 3531	Neveseri

Prime

The prime form of this scale is Scale 759

Scale 759

Katalyllic

Complement

The octatonic modal family [3813, 1977, 759, 2427, 3261, 1839, 2967, 3531] (Forte: 8-14) is the complement of the tetratonic modal family [141, 417, 1059, 2577] (Forte: 4-14)

Inverse

The inverse of a scale is a reflection using the root as its axis. The inverse of 3813 is 1263

Scale 1263

Stynyllic

Interval Matrix

Each row is a generic interval, cells contain the specific size of each generic. Useful for identifying contradictions and ambiguities.

Contradictions (34)

Ambiguities(56)

Hierarchizability

Based on the work of Niels Verosky, hierarchizability is the measure of repeated patterns with "place-finding" remainder bits, applied recursively to the binary representation of a scale. For a full explanation, read Niels' paper, Hierarchizability as a Predictor of Scale Candidacy. The variable k is the maximum number of remainders allowed at each level of recursion, for them to count as an increment of hierarchizability. A high hierarchizability score is a good indicator of scale candidacy, ie a measure of usefulness for producing pleasing music. There is a strong correlation between scales with maximal hierarchizability and scales that are in popular use in a variety of world musical traditions.

k	Hierarchizability	Breakdown Pattern
1	1	`101001110111`
2	3	`00([11]0[11])([11]0[11])`
3	3	`00([11]0[11])([11]0[11])`
4	3	`00([11]0[11])([11]0[11])`
5	3	`00([11]0[11])([11]0[11])`

Enantiomorph

Only scales that are chiral will have an enantiomorph. Scale 3813 is chiral, and its enantiomorph is scale 1263

Scale 1263

Stynyllic

Center of Gravity

If tones of the scale are imagined as identical physical objects spaced around a unit circle, the center of gravity is the point where the scale is balanced.

Position with origin in the center	(-0.1875, -0.016747)
Distance from Center	0.188246
Angle in degrees measured clockwise starting from the root.	275.104
Angle in cents 100 cents = 1 semitone.	917.013333

Transformations:

In the abbreviation, the subscript number after "T" is the number of semitones of tranposition, "M" means the pitch class is multiplied by 5, and "I" means the result is inverted. Operation is an identical way to express the same thing; the syntax is <a,b> where each tone of the set x is transformed by the equation y = ax + b. A note about the multipliers: multiplying by 1 changes nothing, multiplying by 11 produces the same result as inversion. 5 is the only non-degenerate multiplier, with the multiplier 7 producing the inverse of 5.

Abbrev	Operation	Result	Abbrev	Operation	Result
T₀	<1,0>	3813	T₀I	<11,0>	1263
T₁	<1,1>	3531	T₁I	<11,1>	2526
T₂	<1,2>	2967	T₂I	<11,2>	957
T₃	<1,3>	1839	T₃I	<11,3>	1914
T₄	<1,4>	3678	T₄I	<11,4>	3828
T₅	<1,5>	3261	T₅I	<11,5>	3561
T₆	<1,6>	2427	T₆I	<11,6>	3027
T₇	<1,7>	759	T₇I	<11,7>	1959
T₈	<1,8>	1518	T₈I	<11,8>	3918
T₉	<1,9>	3036	T₉I	<11,9>	3741
T₁₀	<1,10>	1977	T₁₀I	<11,10>	3387
T₁₁	<1,11>	3954	T₁₁I	<11,11>	2679
Abbrev	Operation	Result	Abbrev	Operation	Result
T₀M	<5,0>	3783	T₀MI	<7,0>	3183
T₁M	<5,1>	3471	T₁MI	<7,1>	2271
T₂M	<5,2>	2847	T₂MI	<7,2>	447
T₃M	<5,3>	1599	T₃MI	<7,3>	894
T₄M	<5,4>	3198	T₄MI	<7,4>	1788
T₅M	<5,5>	2301	T₅MI	<7,5>	3576
T₆M	<5,6>	507	T₆MI	<7,6>	3057
T₇M	<5,7>	1014	T₇MI	<7,7>	2019
T₈M	<5,8>	2028	T₈MI	<7,8>	4038
T₉M	<5,9>	4056	T₉MI	<7,9>	3981
T₁₀M	<5,10>	4017	T₁₀MI	<7,10>	3867
T₁₁M	<5,11>	3939	T₁₁MI	<7,11>	3639

The transformations that map this set to itself are: T₀

Nearby Scales:

These are other scales that are similar to this one, created by adding a tone, removing a tone, or moving one note up or down a semitone.

Scale 3815				Mylygic
Scale 3809				YELian
Scale 3811				Epogyllic
Scale 3817				Zoryllic
Scale 3821				Diminishing Nonamode 8th Rotation
Scale 3829				Taishikicho
Scale 3781				Gyphian
Scale 3797				Spanish Octamode 8th Rotation
Scale 3749				Raga Sorati
Scale 3685				Kodian
Scale 3941				Stathyllic
Scale 4069				Starygic
Scale 3301				Chromatic Mixolydian Inverse
Scale 3557				Thycryllic
Scale 2789				Zolian
Scale 1765				Lonian

This scale analysis was created by Ian Ring, Canadian Composer of works for Piano, and total music theory nerd. Scale notation generated by VexFlow and Lilypond, graph visualization by Graphviz, audio by TiMIDIty and FFMPEG. All other diagrams and visualizations are © Ian Ring. Some scale names used on this and other pages are ©2005 William Zeitler (http://allthescales.org) used with permission.

Pitch spelling algorithm employed here is adapted from a method by Uzay Bora, Baris Tekin Tezel, and Alper Vahaplar. (DOI, Patent owner: Dokuz Eylül University, Used with Permission.

Tons of background resources contributed to the production of this summary; for a list of these peruse this Bibliography. Special thanks to Richard Repp for helping with technical accuracy, and George Howlett for assistance with naming the Carnatic ragas. Thanks to Niels Verosky for collaborating on the Hierarchizability diagrams. Thanks to u/howaboot for inventing the Center of Gravity metrics.