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Scale 1981: "Houseini"

Scale 1981: Houseini, 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

Unknown / Unsorted
Houseini
Western Mixed
Modes of Major Pentatonic Mixed
Zeitler
Gadygic

Analysis

Cardinality

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

9 (enneatonic)

Pitch Class Set

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

{0,2,3,4,5,7,8,9,10}

Forte Number

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

9-9

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.

[0]

Palindromicity

A palindromic scale has the same pattern of intervals both ascending and descending.

yes

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.

6 (multihemitonic)

Cohemitonia

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

4 (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.

8

Prime Form

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

no
prime: 1519

Generator

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

generator: 5
origin: 4

Deep Scale

A deep scale is one where the interval vector has 6 different digits.

no

Interval Formula

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

[2, 1, 1, 1, 2, 1, 1, 1, 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.

<6, 7, 6, 6, 8, 3>

Interval Spectrum

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

p8m6n6s7d6t3

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

Spectra Variation

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

1.333

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.

2.799

Polygon Perimeter

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

6.106

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.

[0]

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, 83, 168)

Generator

This scale has a generator of 5, originating on 4.

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 TriadsC{0,4,7}342.21
D♯{3,7,10}342.43
F{5,9,0}342.29
G♯{8,0,3}342.21
A♯{10,2,5}242.57
Minor Triadscm{0,3,7}342.29
dm{2,5,9}342.43
fm{5,8,0}342.21
gm{7,10,2}242.57
am{9,0,4}342.21
Augmented TriadsC+{0,4,8}442
Diminished Triads{2,5,8}242.57
{4,7,10}242.57
{9,0,3}242.57
Parsimonious Voice Leading Between Common Triads of Scale 1981. Created by Ian Ring ©2019 cm cm C C cm->C D# D# cm->D# G# G# cm->G# C+ C+ C->C+ C->e° fm fm C+->fm C+->G# am am C+->am dm dm d°->dm d°->fm F F dm->F A# A# dm->A# D#->e° gm gm D#->gm fm->F F->am gm->A# G#->a° a°->am

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.

Diameter4
Radius4
Self-Centeredyes

Modes

Modes are the rotational transformation of this scale. Scale 1981 can be rotated to make 8 other scales. The 1st mode is itself.

2nd mode:
Scale 1519
Scale 1519: Locrian/Aeolian Mixed, Ian Ring Music TheoryLocrian/Aeolian MixedThis is the prime mode
3rd mode:
Scale 2807
Scale 2807: Zylygic, Ian Ring Music TheoryZylygic
4th mode:
Scale 3451
Scale 3451: Garygic, Ian Ring Music TheoryGarygic
5th mode:
Scale 3773
Scale 3773: Raga Malgunji, Ian Ring Music TheoryRaga Malgunji
6th mode:
Scale 1967
Scale 1967: Diatonic Dorian Mixed, Ian Ring Music TheoryDiatonic Dorian Mixed
7th mode:
Scale 3031
Scale 3031: Epithygic, Ian Ring Music TheoryEpithygic
8th mode:
Scale 3563
Scale 3563: Ionoptygic, Ian Ring Music TheoryIonoptygic
9th mode:
Scale 3829
Scale 3829: Taishikicho, Ian Ring Music TheoryTaishikicho

Prime

The prime form of this scale is Scale 1519

Scale 1519Scale 1519: Locrian/Aeolian Mixed, Ian Ring Music TheoryLocrian/Aeolian Mixed

Complement

The enneatonic modal family [1981, 1519, 2807, 3451, 3773, 1967, 3031, 3563, 3829] (Forte: 9-9) is the complement of the tritonic modal family [133, 161, 1057] (Forte: 3-9)

Inverse

The inverse of a scale is a reflection using the root as its axis. The inverse of 1981 is itself, because it is a palindromic scale!

Scale 1981Scale 1981: Houseini, Ian Ring Music TheoryHouseini

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> 1981       T0I <11,0> 1981
T1 <1,1> 3962      T1I <11,1> 3962
T2 <1,2> 3829      T2I <11,2> 3829
T3 <1,3> 3563      T3I <11,3> 3563
T4 <1,4> 3031      T4I <11,4> 3031
T5 <1,5> 1967      T5I <11,5> 1967
T6 <1,6> 3934      T6I <11,6> 3934
T7 <1,7> 3773      T7I <11,7> 3773
T8 <1,8> 3451      T8I <11,8> 3451
T9 <1,9> 2807      T9I <11,9> 2807
T10 <1,10> 1519      T10I <11,10> 1519
T11 <1,11> 3038      T11I <11,11> 3038
Abbrev Operation Result Abbrev Operation Result
T0M <5,0> 3871      T0MI <7,0> 3871
T1M <5,1> 3647      T1MI <7,1> 3647
T2M <5,2> 3199      T2MI <7,2> 3199
T3M <5,3> 2303      T3MI <7,3> 2303
T4M <5,4> 511      T4MI <7,4> 511
T5M <5,5> 1022      T5MI <7,5> 1022
T6M <5,6> 2044      T6MI <7,6> 2044
T7M <5,7> 4088      T7MI <7,7> 4088
T8M <5,8> 4081      T8MI <7,8> 4081
T9M <5,9> 4067      T9MI <7,9> 4067
T10M <5,10> 4039      T10MI <7,10> 4039
T11M <5,11> 3983      T11MI <7,11> 3983

The transformations that map this set to itself are: T0, T0I

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 1983Scale 1983: Soryllian, Ian Ring Music TheorySoryllian
Scale 1977Scale 1977: Dagyllic, Ian Ring Music TheoryDagyllic
Scale 1979Scale 1979: Aeradygic, Ian Ring Music TheoryAeradygic
Scale 1973Scale 1973: Zyryllic, Ian Ring Music TheoryZyryllic
Scale 1965Scale 1965: Raga Mukhari, Ian Ring Music TheoryRaga Mukhari
Scale 1949Scale 1949: Mathyllic, Ian Ring Music TheoryMathyllic
Scale 2013Scale 2013: Mocrygic, Ian Ring Music TheoryMocrygic
Scale 2045Scale 2045: Katogyllian, Ian Ring Music TheoryKatogyllian
Scale 1853Scale 1853: Maryllic, Ian Ring Music TheoryMaryllic
Scale 1917Scale 1917: Sacrygic, Ian Ring Music TheorySacrygic
Scale 1725Scale 1725: Minor Bebop, Ian Ring Music TheoryMinor Bebop
Scale 1469Scale 1469: Epiryllic, Ian Ring Music TheoryEpiryllic
Scale 957Scale 957: Phronyllic, Ian Ring Music TheoryPhronyllic
Scale 3005Scale 3005: Gycrygic, Ian Ring Music TheoryGycrygic
Scale 4029Scale 4029: Major/Minor Mixed, Ian Ring Music TheoryMajor/Minor Mixed

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.