The Exciting Universe Of Music Theory

presents

more than you ever wanted to know about...

Scale 2949: "SIKian"

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).

Analysis

Cardinality Cardinality is the count of how many pitches are in the scale.	6 (hexatonic)
Pitch Class Set The tones in this scale, expressed as numbers from 0 to 11	{0,2,7,8,9,11}
Forte Number A code assigned by theorist Allen Forte, for this pitch class set and all of its transpositional (rotation) and inversional (reflection) transformations.	6-Z11
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: 1083
Hemitonia A hemitone is two tones separated by a semitone interval. Hemitonia describes how many such hemitones exist.	3 (trihemitonic)
Cohemitonia A cohemitone is an instance of two adjacent hemitones. Cohemitonia describes how many such cohemitones exist.	1 (uncohemitonic)
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.	3
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.	6
Prime Form Describes if this scale is in prime form, using the Starr/Rahn algorithm.	no prime: 183
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, 5, 1, 1, 2, 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.	<3, 3, 3, 2, 3, 1>
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.	<0.6, 0.5, 0.6, 0, 0.6, 0.333>
Interval Spectrum The same as the Interval Vector, but expressed in a syntax used by Howard Hanson.	p³m²n³s³d³t
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> = {1,2,5} <2> = {2,3,6,7} <3> = {4,5,7,8} <4> = {5,6,9,10} <5> = {7,10,11}
Spectra Variation Determined by the Distribution Spectra; this is the sum of all spectrum widths divided by the scale cardinality.	3.667
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.	1.866
Polygon Perimeter Perimeter of the polygon described by vertices placed for each tone of the scale dodecimetrically around a unit circle.	5.485
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.	0.372678
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.	(27, 11, 59)
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.	0.415
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.	0.213

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	G	{7,11,2}	1	1	0.5
Diminished Triads	g♯°	{8,11,2}	1	1	0.5

The following pitch classes are not present in any of the common triads: {0,9}

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	1
Radius	1
Self-Centered	yes

Modes

Modes are the rotational transformation of this scale. Scale 2949 can be rotated to make 5 other scales. The 1st mode is itself.

2nd mode: Scale 1761	KUQian
3rd mode: Scale 183	BEBian	This is the prime mode
4th mode: Scale 2139	NAMian
5th mode: Scale 3117	TIJian
6th mode: Scale 1803	LAPian

Prime

The prime form of this scale is Scale 183

Scale 183

BEBian

Complement

The hexatonic modal family [2949, 1761, 183, 2139, 3117, 1803] (Forte: 6-Z11) is the complement of the hexatonic modal family [303, 753, 1929, 2199, 3147, 3621] (Forte: 6-Z40)

Inverse

The inverse of a scale is a reflection using the root as its axis. The inverse of 2949 is 1083

Scale 1083

GOYian

Interval Matrix

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

Contradictions (27)

Ambiguities(11)

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	`101000011101`
2	1	`101000011101`
3	1	`101000011101`
4	1	`101000011101`
5	1	`101000011101`

Enantiomorph

Only scales that are chiral will have an enantiomorph. Scale 2949 is chiral, and its enantiomorph is scale 1083

Scale 1083

GOYian

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	(-0.333333, -0.166667)
Distance from Center	0.372678
Angle in degrees measured clockwise starting from the root.	296.565
Angle in cents 100 cents = 1 semitone.	988.55

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>	2949	T₀I	<11,0>	1083
T₁	<1,1>	1803	T₁I	<11,1>	2166
T₂	<1,2>	3606	T₂I	<11,2>	237
T₃	<1,3>	3117	T₃I	<11,3>	474
T₄	<1,4>	2139	T₄I	<11,4>	948
T₅	<1,5>	183	T₅I	<11,5>	1896
T₆	<1,6>	366	T₆I	<11,6>	3792
T₇	<1,7>	732	T₇I	<11,7>	3489
T₈	<1,8>	1464	T₈I	<11,8>	2883
T₉	<1,9>	2928	T₉I	<11,9>	1671
T₁₀	<1,10>	1761	T₁₀I	<11,10>	3342
T₁₁	<1,11>	3522	T₁₁I	<11,11>	2589
Abbrev	Operation	Result	Abbrev	Operation	Result
T₀M	<5,0>	3729	T₀MI	<7,0>	303
T₁M	<5,1>	3363	T₁MI	<7,1>	606
T₂M	<5,2>	2631	T₂MI	<7,2>	1212
T₃M	<5,3>	1167	T₃MI	<7,3>	2424
T₄M	<5,4>	2334	T₄MI	<7,4>	753
T₅M	<5,5>	573	T₅MI	<7,5>	1506
T₆M	<5,6>	1146	T₆MI	<7,6>	3012
T₇M	<5,7>	2292	T₇MI	<7,7>	1929
T₈M	<5,8>	489	T₈MI	<7,8>	3858
T₉M	<5,9>	978	T₉MI	<7,9>	3621
T₁₀M	<5,10>	1956	T₁₀MI	<7,10>	3147
T₁₁M	<5,11>	3912	T₁₁MI	<7,11>	2199

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 2951				SILian
Scale 2945				SIHian
Scale 2947				SIJian
Scale 2953				Ionylimic
Scale 2957				Thygian
Scale 2965				Darian
Scale 2981				Ionolian
Scale 3013				Thynian
Scale 2821				RUKian
Scale 2885				Byrimic
Scale 2693				Lahuzu 5 Tone Type 3
Scale 2437				PAFian
Scale 3461				VODian
Scale 3973				ZEHian
Scale 901				BOFian
Scale 1925				LUMian

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.

Scale 2949: "SIKian"

Bracelet Diagram

Tonnetz Diagram

Analysis

Cardinality

Pitch Class Set

Proportional Saturation Vector

Polygon Perimeter

Centre of Gravity Distance

Heteromorphic Profile

Coherence Quotient

Sameness Quotient