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Scale 1411: "IROian"

Scale 1411: IROian, 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.

5 (pentatonic)

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: 107


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.

[1, 6, 1, 2, 2]

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, 2, 2, 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.

<0.5, 0.5, 0.5, 0, 0.5, 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> = {1,2,6}
<2> = {3,4,7}
<3> = {5,8,9}
<4> = {6,10,11}

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.

(14, 1, 32)

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

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 TypeTriad*Pitch ClassesDegreeEccentricityCloseness Centrality
Diminished Triads{7,10,1}000

The following pitch classes are not present in any of the common triads: {0,8}

Since there is only one common triad in this scale, there are no opportunities for parsimonious voice leading between triads.


Modes are the rotational transformation of this scale. Scale 1411 can be rotated to make 4 other scales. The 1st mode is itself.

2nd mode:
Scale 2753
Scale 2753: RITian, Ian Ring Music TheoryRITian
3rd mode:
Scale 107
Scale 107: ANSian, Ian Ring Music TheoryANSianThis is the prime mode
4th mode:
Scale 2101
Scale 2101: MUQian, Ian Ring Music TheoryMUQian
5th mode:
Scale 1549
Scale 1549: JOQian, Ian Ring Music TheoryJOQian


The prime form of this scale is Scale 107

Scale 107Scale 107: ANSian, Ian Ring Music TheoryANSian


The pentatonic modal family [1411, 2753, 107, 2101, 1549] (Forte: 5-Z12) is the complement of the heptatonic modal family [671, 997, 1273, 2383, 3239, 3667, 3881] (Forte: 7-Z12)


The inverse of a scale is a reflection using the root as its axis. The inverse of 1411 is 2101

Scale 2101Scale 2101: MUQian, Ian Ring Music TheoryMUQian


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> 1411       T0I <11,0> 2101
T1 <1,1> 2822      T1I <11,1> 107
T2 <1,2> 1549      T2I <11,2> 214
T3 <1,3> 3098      T3I <11,3> 428
T4 <1,4> 2101      T4I <11,4> 856
T5 <1,5> 107      T5I <11,5> 1712
T6 <1,6> 214      T6I <11,6> 3424
T7 <1,7> 428      T7I <11,7> 2753
T8 <1,8> 856      T8I <11,8> 1411
T9 <1,9> 1712      T9I <11,9> 2822
T10 <1,10> 3424      T10I <11,10> 1549
T11 <1,11> 2753      T11I <11,11> 3098
Abbrev Operation Result Abbrev Operation Result
T0M <5,0> 2101      T0MI <7,0> 1411
T1M <5,1> 107      T1MI <7,1> 2822
T2M <5,2> 214      T2MI <7,2> 1549
T3M <5,3> 428      T3MI <7,3> 3098
T4M <5,4> 856      T4MI <7,4> 2101
T5M <5,5> 1712      T5MI <7,5> 107
T6M <5,6> 3424      T6MI <7,6> 214
T7M <5,7> 2753      T7MI <7,7> 428
T8M <5,8> 1411       T8MI <7,8> 856
T9M <5,9> 2822      T9MI <7,9> 1712
T10M <5,10> 1549      T10MI <7,10> 3424
T11M <5,11> 3098      T11MI <7,11> 2753

The transformations that map this set to itself are: T0, T8I, T8M, 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 1409Scale 1409: IMSian, Ian Ring Music TheoryIMSian
Scale 1413Scale 1413: IRUian, Ian Ring Music TheoryIRUian
Scale 1415Scale 1415: IMPian, Ian Ring Music TheoryIMPian
Scale 1419Scale 1419: Raga Kashyapi, Ian Ring Music TheoryRaga Kashyapi
Scale 1427Scale 1427: Lolimic, Ian Ring Music TheoryLolimic
Scale 1443Scale 1443: Raga Phenadyuti, Ian Ring Music TheoryRaga Phenadyuti
Scale 1475Scale 1475: UFFian, Ian Ring Music TheoryUFFian
Scale 1283Scale 1283: HURian, Ian Ring Music TheoryHURian
Scale 1347Scale 1347: IGOian, Ian Ring Music TheoryIGOian
Scale 1155Scale 1155: ADWian, Ian Ring Music TheoryADWian
Scale 1667Scale 1667: KEKian, Ian Ring Music TheoryKEKian
Scale 1923Scale 1923: LULian, Ian Ring Music TheoryLULian
Scale 387Scale 387: CIWian, Ian Ring Music TheoryCIWian
Scale 899Scale 899: FOQian, Ian Ring Music TheoryFOQian
Scale 2435Scale 2435: Raga Deshgaur, Ian Ring Music TheoryRaga Deshgaur
Scale 3459Scale 3459: VOCian, Ian Ring Music TheoryVOCian

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.