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Scale 787: "Aeolapritonic"

Scale 787: Aeolapritonic, 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).

Common Names

Zeitler
Aeolapritonic
Dozenal
Errian

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

{0,1,4,8,9}

Forte Number

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

5-21

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: 2329

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.

3

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: 307

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, 3, 4, 1, 3]

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, 2, 4, 2, 0>

Interval Spectrum

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

p2m4n2d2

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

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.

1.933

Polygon Perimeter

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

5.596

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.

(1, 8, 30)

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
Major TriadsA{9,1,4}221
Minor Triadsc♯m{1,4,8}221
am{9,0,4}221
Augmented TriadsC+{0,4,8}221
Parsimonious Voice Leading Between Common Triads of Scale 787. Created by Ian Ring ©2019 C+ C+ c#m c#m C+->c#m am am C+->am A A c#m->A am->A

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.

Diameter2
Radius2
Self-Centeredyes

Modes

Modes are the rotational transformation of this scale. Scale 787 can be rotated to make 4 other scales. The 1st mode is itself.

2nd mode:
Scale 2441
Scale 2441: Kyritonic, Ian Ring Music TheoryKyritonic
3rd mode:
Scale 817
Scale 817: Zothitonic, Ian Ring Music TheoryZothitonic
4th mode:
Scale 307
Scale 307: Raga Megharanjani, Ian Ring Music TheoryRaga MegharanjaniThis is the prime mode
5th mode:
Scale 2201
Scale 2201: Ionagitonic, Ian Ring Music TheoryIonagitonic

Prime

The prime form of this scale is Scale 307

Scale 307Scale 307: Raga Megharanjani, Ian Ring Music TheoryRaga Megharanjani

Complement

The pentatonic modal family [787, 2441, 817, 307, 2201] (Forte: 5-21) is the complement of the heptatonic modal family [823, 883, 1843, 2459, 2489, 2969, 3277] (Forte: 7-21)

Inverse

The inverse of a scale is a reflection using the root as its axis. The inverse of 787 is 2329

Scale 2329Scale 2329: Styditonic, Ian Ring Music TheoryStyditonic

Enantiomorph

Only scales that are chiral will have an enantiomorph. Scale 787 is chiral, and its enantiomorph is scale 2329

Scale 2329Scale 2329: Styditonic, Ian Ring Music TheoryStyditonic

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> 787       T0I <11,0> 2329
T1 <1,1> 1574      T1I <11,1> 563
T2 <1,2> 3148      T2I <11,2> 1126
T3 <1,3> 2201      T3I <11,3> 2252
T4 <1,4> 307      T4I <11,4> 409
T5 <1,5> 614      T5I <11,5> 818
T6 <1,6> 1228      T6I <11,6> 1636
T7 <1,7> 2456      T7I <11,7> 3272
T8 <1,8> 817      T8I <11,8> 2449
T9 <1,9> 1634      T9I <11,9> 803
T10 <1,10> 3268      T10I <11,10> 1606
T11 <1,11> 2441      T11I <11,11> 3212
Abbrev Operation Result Abbrev Operation Result
T0M <5,0> 817      T0MI <7,0> 409
T1M <5,1> 1634      T1MI <7,1> 818
T2M <5,2> 3268      T2MI <7,2> 1636
T3M <5,3> 2441      T3MI <7,3> 3272
T4M <5,4> 787       T4MI <7,4> 2449
T5M <5,5> 1574      T5MI <7,5> 803
T6M <5,6> 3148      T6MI <7,6> 1606
T7M <5,7> 2201      T7MI <7,7> 3212
T8M <5,8> 307      T8MI <7,8> 2329
T9M <5,9> 614      T9MI <7,9> 563
T10M <5,10> 1228      T10MI <7,10> 1126
T11M <5,11> 2456      T11MI <7,11> 2252

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

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 785Scale 785: Aeoloric, Ian Ring Music TheoryAeoloric
Scale 789Scale 789: Zogitonic, Ian Ring Music TheoryZogitonic
Scale 791Scale 791: Aeoloptimic, Ian Ring Music TheoryAeoloptimic
Scale 795Scale 795: Aeologimic, Ian Ring Music TheoryAeologimic
Scale 771Scale 771: Esoian, Ian Ring Music TheoryEsoian
Scale 779Scale 779: Etrian, Ian Ring Music TheoryEtrian
Scale 803Scale 803: Loritonic, Ian Ring Music TheoryLoritonic
Scale 819Scale 819: Augmented Inverse, Ian Ring Music TheoryAugmented Inverse
Scale 851Scale 851: Raga Hejjajji, Ian Ring Music TheoryRaga Hejjajji
Scale 915Scale 915: Raga Kalagada, Ian Ring Music TheoryRaga Kalagada
Scale 531Scale 531: Degian, Ian Ring Music TheoryDegian
Scale 659Scale 659: Raga Rasika Ranjani, Ian Ring Music TheoryRaga Rasika Ranjani
Scale 275Scale 275: Dalic, Ian Ring Music TheoryDalic
Scale 1299Scale 1299: Aerophitonic, Ian Ring Music TheoryAerophitonic
Scale 1811Scale 1811: Kyptimic, Ian Ring Music TheoryKyptimic
Scale 2835Scale 2835: Ionygimic, Ian Ring Music TheoryIonygimic

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.