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Scale 2097: "MUNian"

Scale 2097: MUNian, Ian Ring Music Theory

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).



Cardinality is the count of how many pitches are in the scale.

4 (tetratonic)

Pitch Class Set

The tones in this scale, expressed as numbers from 0 to 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.


Rotational Symmetry

Some scales have rotational symmetry, sometimes known as "limited transposition". If there are any rotational symmetries, these are the intervals of periodicity.


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.



A palindromic scale has the same pattern of intervals both ascending and descending.



A chiral scale can not be transformed into its inverse by rotation. If a scale is chiral, then it has an enantiomorph.



A hemitone is two tones separated by a semitone interval. Hemitonia describes how many such hemitones exist.

2 (dihemitonic)


A cohemitone is an instance of two adjacent hemitones. Cohemitonia describes how many such cohemitones exist.

0 (ancohemitonic)


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.



Modes are the rotational transformations of this scale. This number does not include the scale itself, so the number is usually one less than its cardinality; unless there are rotational symmetries then there are even fewer modes.


Prime Form

Describes if this scale is in prime form, using the Starr/Rahn algorithm.

prime: 99


Indicates if the scale can be constructed using a generator, and an origin.


Deep Scale

A deep scale is one where the interval vector has 6 different digits, an indicator of maximum hierarchization.


Interval Structure

Defines the scale as the sequence of intervals between one tone and the next.

[4, 1, 6, 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.

<2, 0, 0, 1, 2, 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.

<0.667, 0, 0, 0.333, 0.667, 0.5>

Interval Spectrum

The same as the Interval Vector, but expressed in a syntax used by Howard Hanson.


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> = {1,4,6}
<2> = {5,7}
<3> = {6,8,11}

Spectra Variation

Determined by the Distribution Spectra; this is the sum of all spectrum widths divided by the scale cardinality.


Maximally Even

A scale is maximally even if the tones are optimally spaced apart from each other.


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.


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.


Polygon Perimeter

Perimeter of the polygon described by vertices placed for each tone of the scale dodecimetrically around a unit circle.


Myhill Property

A scale has Myhill Property if the Distribution Spectra have exactly two specific intervals for every generic interval.



A scale is balanced if the distribution of its tones would satisfy the "centrifuge problem", ie are placed such that it would balance on its centre point.


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.



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".


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.

(4, 1, 14)

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.


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.



This scale has no generator.

Common Triads

There are no common triads (major, minor, augmented and diminished) that can be formed using notes in this scale.


Modes are the rotational transformation of this scale. Scale 2097 can be rotated to make 3 other scales. The 1st mode is itself.

2nd mode:
Scale 387
Scale 387: CIWian, Ian Ring Music TheoryCIWian
3rd mode:
Scale 2241
Scale 2241: NOXian, Ian Ring Music TheoryNOXian
4th mode:
Scale 99
Scale 99: IPRian, Ian Ring Music TheoryIPRianThis is the prime mode


The prime form of this scale is Scale 99

Scale 99Scale 99: IPRian, Ian Ring Music TheoryIPRian


The tetratonic modal family [2097, 387, 2241, 99] (Forte: 4-8) is the complement of the octatonic modal family [927, 999, 2511, 2547, 3303, 3321, 3699, 3897] (Forte: 8-8)


The inverse of a scale is a reflection using the root as its axis. The inverse of 2097 is 387

Scale 387Scale 387: CIWian, Ian Ring Music TheoryCIWian


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

Abbrev Operation Result Abbrev Operation Result
T0 <1,0> 2097       T0I <11,0> 387
T1 <1,1> 99      T1I <11,1> 774
T2 <1,2> 198      T2I <11,2> 1548
T3 <1,3> 396      T3I <11,3> 3096
T4 <1,4> 792      T4I <11,4> 2097
T5 <1,5> 1584      T5I <11,5> 99
T6 <1,6> 3168      T6I <11,6> 198
T7 <1,7> 2241      T7I <11,7> 396
T8 <1,8> 387      T8I <11,8> 792
T9 <1,9> 774      T9I <11,9> 1584
T10 <1,10> 1548      T10I <11,10> 3168
T11 <1,11> 3096      T11I <11,11> 2241
Abbrev Operation Result Abbrev Operation Result
T0M <5,0> 387      T0MI <7,0> 2097
T1M <5,1> 774      T1MI <7,1> 99
T2M <5,2> 1548      T2MI <7,2> 198
T3M <5,3> 3096      T3MI <7,3> 396
T4M <5,4> 2097       T4MI <7,4> 792
T5M <5,5> 99      T5MI <7,5> 1584
T6M <5,6> 198      T6MI <7,6> 3168
T7M <5,7> 396      T7MI <7,7> 2241
T8M <5,8> 792      T8MI <7,8> 387
T9M <5,9> 1584      T9MI <7,9> 774
T10M <5,10> 3168      T10MI <7,10> 1548
T11M <5,11> 2241      T11MI <7,11> 3096

The transformations that map this set to itself are: T0, T4I, T4M, T0MI

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 2099Scale 2099: Raga Megharanji, Ian Ring Music TheoryRaga Megharanji
Scale 2101Scale 2101: MUQian, Ian Ring Music TheoryMUQian
Scale 2105Scale 2105: RIGian, Ian Ring Music TheoryRIGian
Scale 2081Scale 2081: MODian, Ian Ring Music TheoryMODian
Scale 2089Scale 2089: MUJian, Ian Ring Music TheoryMUJian
Scale 2065Scale 2065: MOTian, Ian Ring Music TheoryMOTian
Scale 2129Scale 2129: Raga Nigamagamini, Ian Ring Music TheoryRaga Nigamagamini
Scale 2161Scale 2161: NEZian, Ian Ring Music TheoryNEZian
Scale 2225Scale 2225: Ionian Pentatonic, Ian Ring Music TheoryIonian Pentatonic
Scale 2353Scale 2353: Raga Girija, Ian Ring Music TheoryRaga Girija
Scale 2609Scale 2609: Raga Bhinna Shadja, Ian Ring Music TheoryRaga Bhinna Shadja
Scale 3121Scale 3121: TILian, Ian Ring Music TheoryTILian
Scale 49Scale 49: AGUian, Ian Ring Music TheoryAGUian
Scale 1073Scale 1073: GOSian, Ian Ring Music TheoryGOSian

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 ( used with permission.

Pitch spelling algorithm employed here is adapted from a method by Uzay Bora, Baris Tekin Tezel, and Alper Vahaplar. (An algorithm for spelling the pitches of any musical scale) Contact authors Patent owner: Dokuz Eylül University, Used with Permission. Contact TTO

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 the Carnatic ragas.