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# Scale 3831: "Ionyllian" ### 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).

Zeitler
Ionyllian
Dozenal
YIYian

## Analysis

#### Cardinality

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

10 (decatonic)

#### Pitch Class Set

The tones in this scale, expressed as numbers from 0 to 11

{0,1,2,4,5,6,7,9,10,11}

#### Forte Number

A code assigned by theorist Allen Forte, for this pitch class set and all of its transpositional (rotation) and inversional (reflection) transformations.

10-5

#### 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.

[5.5]

#### 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.

no

#### Hemitonia

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

8 (multihemitonic)

#### Cohemitonia

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

6 (multicohemitonic)

#### 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.

1

#### Modes

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.

9

#### Prime Form

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

no
prime: 1983

#### Generator

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

generator: 5
origin: 1

#### 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.

[1, 1, 2, 1, 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.

<8, 8, 8, 8, 9, 4>

#### 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, 0, 0, 0, 1, 0>

#### Interval Spectrum

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

p9m8n8s8d8t4

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

#### Spectra Variation

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

1

#### 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.

yes

#### 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.

2.866

#### Polygon Perimeter

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

6.141

#### Myhill Property

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

no

#### Balanced

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.

no

#### 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.



#### 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".

Proper

#### 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.

(0, 96, 177)

#### 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.

0.872

#### 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.

0.563

## Generator

This scale has a generator of 5, originating on 1.

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

D{2,6,9}352.59
F{5,9,0}352.77
F♯{6,10,1}452.41
G{7,11,2}352.86
A{9,1,4}452.68
A♯{10,2,5}452.5
em{4,7,11}352.95
f♯m{6,9,1}452.5
gm{7,10,2}452.68
am{9,0,4}352.86
a♯m{10,1,5}452.41
bm{11,2,6}352.77
D+{2,6,10}552.41
{4,7,10}253.05
f♯°{6,9,0}253.05
{7,10,1}252.86
a♯°{10,1,4}252.86
{11,2,5}253.05

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 5 yes

## Modes

Modes are the rotational transformation of this scale. Scale 3831 can be rotated to make 9 other scales. The 1st mode is itself.

 2nd mode:Scale 3963 Aeoryllian 3rd mode:Scale 4029 Major/Minor Mixed 4th mode:Scale 2031 Gadyllian 5th mode:Scale 3063 Solyllian 6th mode:Scale 3579 Zyphyllian 7th mode:Scale 3837 Minor Pentatonic With Leading Tones 8th mode:Scale 1983 Soryllian This is the prime mode 9th mode:Scale 3039 Godyllian 10th mode:Scale 3567 Epityllian

## Prime

The prime form of this scale is Scale 1983

 Scale 1983 Soryllian

## Complement

The decatonic modal family [3831, 3963, 4029, 2031, 3063, 3579, 3837, 1983, 3039, 3567] (Forte: 10-5) is the complement of the ditonic modal family [33, 129] (Forte: 2-5)

## Inverse

The inverse of a scale is a reflection using the root as its axis. The inverse of 3831 is 3567

 Scale 3567 Epityllian

## 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

Abbrev Operation Result Abbrev Operation Result
T0 <1,0> 3831       T0I <11,0> 3567
T1 <1,1> 3567      T1I <11,1> 3039
T2 <1,2> 3039      T2I <11,2> 1983
T3 <1,3> 1983      T3I <11,3> 3966
T4 <1,4> 3966      T4I <11,4> 3837
T5 <1,5> 3837      T5I <11,5> 3579
T6 <1,6> 3579      T6I <11,6> 3063
T7 <1,7> 3063      T7I <11,7> 2031
T8 <1,8> 2031      T8I <11,8> 4062
T9 <1,9> 4062      T9I <11,9> 4029
T10 <1,10> 4029      T10I <11,10> 3963
T11 <1,11> 3963      T11I <11,11> 3831
Abbrev Operation Result Abbrev Operation Result
T0M <5,0> 4071      T0MI <7,0> 3327
T1M <5,1> 4047      T1MI <7,1> 2559
T2M <5,2> 3999      T2MI <7,2> 1023
T3M <5,3> 3903      T3MI <7,3> 2046
T4M <5,4> 3711      T4MI <7,4> 4092
T5M <5,5> 3327      T5MI <7,5> 4089
T6M <5,6> 2559      T6MI <7,6> 4083
T7M <5,7> 1023      T7MI <7,7> 4071
T8M <5,8> 2046      T8MI <7,8> 4047
T9M <5,9> 4092      T9MI <7,9> 3999
T10M <5,10> 4089      T10MI <7,10> 3903
T11M <5,11> 4083      T11MI <7,11> 3711

The transformations that map this set to itself are: T0, T11I

## 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 3829 Taishikicho Scale 3827 Dorygic Scale 3835 Messiaen Mode 7 Rotation 2 Scale 3839 Chromatic Undecamode 4 Scale 3815 Mylygic Scale 3823 Epinyllian Scale 3799 Aeralygic Scale 3767 Chromatic Bebop Scale 3703 Katalygic Scale 3959 Katagyllian Scale 4087 Chromatic Undecamode 9 Scale 3319 Tholygic Scale 3575 Messiaen Mode 7 Rotation 1 Scale 2807 Zylygic Scale 1783 Youlan

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. (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.