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# Scale 1123: "Iwato" ### 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).

Japanese
Iwato
Zeitler
Lanitonic
Dozenal
Guxian

## Analysis

#### Cardinality

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

{0,1,5,6,10}

#### Forte Number

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

5-20

#### 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: 2245

#### Hemitonia

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

2 (dihemitonic)

#### Cohemitonia

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

0 (ancohemitonic)

#### 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 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.

4

#### Prime Form

Describes if this scale is in prime form, using the Rahn/Ring formula.

no
prime: 355

#### 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.

no

#### Interval Structure

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

[1, 4, 1, 4, 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, 1, 1, 2, 3, 1>

#### Interval Spectrum

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

p3m2nsd2t

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

#### Spectra Variation

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

2.4

#### 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.

1.799

#### Polygon Perimeter

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

5.499

#### Myhill Property

A scale has Myhill Property if the Interval Spectra has 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.

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.

(4, 1, 30)

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

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

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 1 yes

## Modes

Modes are the rotational transformation of this scale. Scale 1123 can be rotated to make 4 other scales. The 1st mode is itself.

 2nd mode:Scale 2609 Raga Bhinna Shadja 3rd mode:Scale 419 Hon-kumoi-joshi 4th mode:Scale 2257 Lydian Pentatonic 5th mode:Scale 397 Aeolian Pentatonic

## Prime

The prime form of this scale is Scale 355

 Scale 355 Aeoloritonic

## Complement

The pentatonic modal family [1123, 2609, 419, 2257, 397] (Forte: 5-20) is the complement of the heptatonic modal family [743, 919, 1849, 2419, 2507, 3257, 3301] (Forte: 7-20)

## Inverse

The inverse of a scale is a reflection using the root as its axis. The inverse of 1123 is 2245

 Scale 2245 Raga Vaijayanti

## Enantiomorph

Only scales that are chiral will have an enantiomorph. Scale 1123 is chiral, and its enantiomorph is scale 2245

 Scale 2245 Raga Vaijayanti

## 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> 1123       T0I <11,0> 2245
T1 <1,1> 2246      T1I <11,1> 395
T2 <1,2> 397      T2I <11,2> 790
T3 <1,3> 794      T3I <11,3> 1580
T4 <1,4> 1588      T4I <11,4> 3160
T5 <1,5> 3176      T5I <11,5> 2225
T6 <1,6> 2257      T6I <11,6> 355
T7 <1,7> 419      T7I <11,7> 710
T8 <1,8> 838      T8I <11,8> 1420
T9 <1,9> 1676      T9I <11,9> 2840
T10 <1,10> 3352      T10I <11,10> 1585
T11 <1,11> 2609      T11I <11,11> 3170
Abbrev Operation Result Abbrev Operation Result
T0M <5,0> 103      T0MI <7,0> 3265
T1M <5,1> 206      T1MI <7,1> 2435
T2M <5,2> 412      T2MI <7,2> 775
T3M <5,3> 824      T3MI <7,3> 1550
T4M <5,4> 1648      T4MI <7,4> 3100
T5M <5,5> 3296      T5MI <7,5> 2105
T6M <5,6> 2497      T6MI <7,6> 115
T7M <5,7> 899      T7MI <7,7> 230
T8M <5,8> 1798      T8MI <7,8> 460
T9M <5,9> 3596      T9MI <7,9> 920
T10M <5,10> 3097      T10MI <7,10> 1840
T11M <5,11> 2099      T11MI <7,11> 3680

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 1121 Guwian Scale 1125 Ionaritonic Scale 1127 Eparimic Scale 1131 Honchoshi Plagal Form Scale 1139 Aerygimic Scale 1091 Pedian Scale 1107 Mogitonic Scale 1059 Gikian Scale 1187 Kokin-joshi Scale 1251 Sylimic Scale 1379 Kycrimic Scale 1635 Sygimic Scale 99 Iprian Scale 611 Anchihoye Scale 2147 Narian Scale 3171 Zythimic

This scale analysis was created by Ian Ring, Canadian Composer of works for Piano, and total music theory nerd. Scale notation generated by VexFlow, graph visualization by Graphviz, and MIDI playback by MIDI.js. 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.