The Exciting Universe Of Music Theory
presents

more than you ever wanted to know about...

Scale 1421: "Raga Trimurti"

Scale 1421: Raga Trimurti, 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

Carnatic
Raga Trimurti
Zeitler
Aeolaphimic
Dozenal
Isoian

Analysis

Cardinality

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

6 (hexatonic)

Pitch Class Set

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

{0,2,3,7,8,10}

Forte Number

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

6-Z26

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]

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.

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.

5

Prime Form

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

no
prime: 427

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.

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

Interval Spectrum

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

p4m3n2s3d2t

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

Spectra Variation

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

2

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.

2.232

Polygon Perimeter

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

5.767

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.

[10]

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, 12, 58)

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 TriadsD♯{3,7,10}221
G♯{8,0,3}131.5
Minor Triadscm{0,3,7}221
gm{7,10,2}131.5
Parsimonious Voice Leading Between Common Triads of Scale 1421. Created by Ian Ring ©2019 cm cm D# D# cm->D# G# G# cm->G# gm gm D#->gm

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.

Diameter3
Radius2
Self-Centeredno
Central Verticescm, D♯
Peripheral Verticesgm, G♯

Triad Polychords

Also known as Bi-Triadic Hexatonics (a term coined by mDecks), and related to Generic Modality Compression (a method for guitar by Mick Goodrick and Tim Miller), these are two common triads that when combined use all the tones in this scale.

There is 1 way that this hexatonic scale can be split into two common triads.


Minor: {7, 10, 2}
Major: {8, 0, 3}

Modes

Modes are the rotational transformation of this scale. Scale 1421 can be rotated to make 5 other scales. The 1st mode is itself.

2nd mode:
Scale 1379
Scale 1379: Kycrimic, Ian Ring Music TheoryKycrimic
3rd mode:
Scale 2737
Scale 2737: Raga Hari Nata, Ian Ring Music TheoryRaga Hari Nata
4th mode:
Scale 427
Scale 427: Raga Suddha Simantini, Ian Ring Music TheoryRaga Suddha SimantiniThis is the prime mode
5th mode:
Scale 2261
Scale 2261: Raga Caturangini, Ian Ring Music TheoryRaga Caturangini
6th mode:
Scale 1589
Scale 1589: Raga Rageshri, Ian Ring Music TheoryRaga Rageshri

Prime

The prime form of this scale is Scale 427

Scale 427Scale 427: Raga Suddha Simantini, Ian Ring Music TheoryRaga Suddha Simantini

Complement

The hexatonic modal family [1421, 1379, 2737, 427, 2261, 1589] (Forte: 6-Z26) is the complement of the hexatonic modal family [679, 917, 1253, 1337, 2387, 3241] (Forte: 6-Z48)

Inverse

The inverse of a scale is a reflection using the root as its axis. The inverse of 1421 is 1589

Scale 1589Scale 1589: Raga Rageshri, Ian Ring Music TheoryRaga Rageshri

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> 1421       T0I <11,0> 1589
T1 <1,1> 2842      T1I <11,1> 3178
T2 <1,2> 1589      T2I <11,2> 2261
T3 <1,3> 3178      T3I <11,3> 427
T4 <1,4> 2261      T4I <11,4> 854
T5 <1,5> 427      T5I <11,5> 1708
T6 <1,6> 854      T6I <11,6> 3416
T7 <1,7> 1708      T7I <11,7> 2737
T8 <1,8> 3416      T8I <11,8> 1379
T9 <1,9> 2737      T9I <11,9> 2758
T10 <1,10> 1379      T10I <11,10> 1421
T11 <1,11> 2758      T11I <11,11> 2842
Abbrev Operation Result Abbrev Operation Result
T0M <5,0> 3101      T0MI <7,0> 1799
T1M <5,1> 2107      T1MI <7,1> 3598
T2M <5,2> 119      T2MI <7,2> 3101
T3M <5,3> 238      T3MI <7,3> 2107
T4M <5,4> 476      T4MI <7,4> 119
T5M <5,5> 952      T5MI <7,5> 238
T6M <5,6> 1904      T6MI <7,6> 476
T7M <5,7> 3808      T7MI <7,7> 952
T8M <5,8> 3521      T8MI <7,8> 1904
T9M <5,9> 2947      T9MI <7,9> 3808
T10M <5,10> 1799      T10MI <7,10> 3521
T11M <5,11> 3598      T11MI <7,11> 2947

The transformations that map this set to itself are: T0, T10I

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 1423Scale 1423: Doptian, Ian Ring Music TheoryDoptian
Scale 1417Scale 1417: Raga Shailaja, Ian Ring Music TheoryRaga Shailaja
Scale 1419Scale 1419: Raga Kashyapi, Ian Ring Music TheoryRaga Kashyapi
Scale 1413Scale 1413: Iruian, Ian Ring Music TheoryIruian
Scale 1429Scale 1429: Bythimic, Ian Ring Music TheoryBythimic
Scale 1437Scale 1437: Sabach ascending, Ian Ring Music TheorySabach ascending
Scale 1453Scale 1453: Aeolian, Ian Ring Music TheoryAeolian
Scale 1485Scale 1485: Minor Romani, Ian Ring Music TheoryMinor Romani
Scale 1293Scale 1293: Huxian, Ian Ring Music TheoryHuxian
Scale 1357Scale 1357: Takemitsu Linea Mode 2, Ian Ring Music TheoryTakemitsu Linea Mode 2
Scale 1165Scale 1165: Gycritonic, Ian Ring Music TheoryGycritonic
Scale 1677Scale 1677: Raga Manavi, Ian Ring Music TheoryRaga Manavi
Scale 1933Scale 1933: Mocrian, Ian Ring Music TheoryMocrian
Scale 397Scale 397: Aeolian Pentatonic, Ian Ring Music TheoryAeolian Pentatonic
Scale 909Scale 909: Katarimic, Ian Ring Music TheoryKatarimic
Scale 2445Scale 2445: Zadimic, Ian Ring Music TheoryZadimic
Scale 3469Scale 3469: Monian, Ian Ring Music TheoryMonian

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.