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Scale 2541: "Algerian"

Scale 2541: Algerian, 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

Exoticisms
Algerian
Unknown / Unsorted
Sabiren
Zeitler
Katadyllic
Dozenal
Porian

Analysis

Cardinality

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

8 (octatonic)

Pitch Class Set

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

{0,2,3,5,6,7,8,11}

Forte Number

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

8-18

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: 1779

Hemitonia

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

5 (multihemitonic)

Cohemitonia

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

2 (dicohemitonic)

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.

7

Prime Form

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

no
prime: 879

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, 2, 1, 1, 1, 3, 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.

<5, 4, 6, 5, 5, 3>

Interval Spectrum

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

p5m5n6s4d5t3

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

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.

2.616

Polygon Perimeter

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

6.002

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.

(12, 59, 138)

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 TriadsG{7,11,2}342.08
G♯{8,0,3}342
B{11,3,6}342.08
Minor Triadscm{0,3,7}342.08
fm{5,8,0}342.23
g♯m{8,11,3}441.92
bm{11,2,6}342.15
Augmented TriadsD♯+{3,7,11}441.85
Diminished Triads{0,3,6}242.46
{2,5,8}242.46
{5,8,11}242.31
g♯°{8,11,2}242.31
{11,2,5}242.38
Parsimonious Voice Leading Between Common Triads of Scale 2541. Created by Ian Ring ©2019 cm cm c°->cm B B c°->B D#+ D#+ cm->D#+ G# G# cm->G# fm fm d°->fm d°->b° Parsimonious Voice Leading Between Common Triads of Scale 2541. Created by Ian Ring ©2019 G D#+->G g#m g#m D#+->g#m D#+->B f°->fm f°->g#m fm->G# g#° g#° G->g#° bm bm G->bm g#°->g#m g#m->G# b°->bm bm->B

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 2541 can be rotated to make 7 other scales. The 1st mode is itself.

2nd mode:
Scale 1659
Scale 1659: Maqam Shadd'araban, Ian Ring Music TheoryMaqam Shadd'araban
3rd mode:
Scale 2877
Scale 2877: Phrylyllic, Ian Ring Music TheoryPhrylyllic
4th mode:
Scale 1743
Scale 1743: Epigyllic, Ian Ring Music TheoryEpigyllic
5th mode:
Scale 2919
Scale 2919: Molyllic, Ian Ring Music TheoryMolyllic
6th mode:
Scale 3507
Scale 3507: Maqam Hijaz, Ian Ring Music TheoryMaqam Hijaz
7th mode:
Scale 3801
Scale 3801: Maptyllic, Ian Ring Music TheoryMaptyllic
8th mode:
Scale 987
Scale 987: Aeraptyllic, Ian Ring Music TheoryAeraptyllic

Prime

The prime form of this scale is Scale 879

Scale 879Scale 879: Aeranyllic, Ian Ring Music TheoryAeranyllic

Complement

The octatonic modal family [2541, 1659, 2877, 1743, 2919, 3507, 3801, 987] (Forte: 8-18) is the complement of the tetratonic modal family [147, 609, 777, 2121] (Forte: 4-18)

Inverse

The inverse of a scale is a reflection using the root as its axis. The inverse of 2541 is 1779

Scale 1779Scale 1779: Zynyllic, Ian Ring Music TheoryZynyllic

Enantiomorph

Only scales that are chiral will have an enantiomorph. Scale 2541 is chiral, and its enantiomorph is scale 1779

Scale 1779Scale 1779: Zynyllic, Ian Ring Music TheoryZynyllic

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> 2541       T0I <11,0> 1779
T1 <1,1> 987      T1I <11,1> 3558
T2 <1,2> 1974      T2I <11,2> 3021
T3 <1,3> 3948      T3I <11,3> 1947
T4 <1,4> 3801      T4I <11,4> 3894
T5 <1,5> 3507      T5I <11,5> 3693
T6 <1,6> 2919      T6I <11,6> 3291
T7 <1,7> 1743      T7I <11,7> 2487
T8 <1,8> 3486      T8I <11,8> 879
T9 <1,9> 2877      T9I <11,9> 1758
T10 <1,10> 1659      T10I <11,10> 3516
T11 <1,11> 3318      T11I <11,11> 2937
Abbrev Operation Result Abbrev Operation Result
T0M <5,0> 3291      T0MI <7,0> 2919
T1M <5,1> 2487      T1MI <7,1> 1743
T2M <5,2> 879      T2MI <7,2> 3486
T3M <5,3> 1758      T3MI <7,3> 2877
T4M <5,4> 3516      T4MI <7,4> 1659
T5M <5,5> 2937      T5MI <7,5> 3318
T6M <5,6> 1779      T6MI <7,6> 2541
T7M <5,7> 3558      T7MI <7,7> 987
T8M <5,8> 3021      T8MI <7,8> 1974
T9M <5,9> 1947      T9MI <7,9> 3948
T10M <5,10> 3894      T10MI <7,10> 3801
T11M <5,11> 3693      T11MI <7,11> 3507

The transformations that map this set to itself are: T0, T6MI

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 2543Scale 2543: Dydygic, Ian Ring Music TheoryDydygic
Scale 2537Scale 2537: Laptian, Ian Ring Music TheoryLaptian
Scale 2539Scale 2539: Half-Diminished Bebop, Ian Ring Music TheoryHalf-Diminished Bebop
Scale 2533Scale 2533: Podian, Ian Ring Music TheoryPodian
Scale 2549Scale 2549: Rydyllic, Ian Ring Music TheoryRydyllic
Scale 2557Scale 2557: Dothygic, Ian Ring Music TheoryDothygic
Scale 2509Scale 2509: Double Harmonic Minor, Ian Ring Music TheoryDouble Harmonic Minor
Scale 2525Scale 2525: Aeolaryllic, Ian Ring Music TheoryAeolaryllic
Scale 2477Scale 2477: Harmonic Minor, Ian Ring Music TheoryHarmonic Minor
Scale 2413Scale 2413: Locrian Natural 2, Ian Ring Music TheoryLocrian Natural 2
Scale 2285Scale 2285: Aerogian, Ian Ring Music TheoryAerogian
Scale 2797Scale 2797: Stalyllic, Ian Ring Music TheoryStalyllic
Scale 3053Scale 3053: Zycrygic, Ian Ring Music TheoryZycrygic
Scale 3565Scale 3565: Aeolorygic, Ian Ring Music TheoryAeolorygic
Scale 493Scale 493: Rygian, Ian Ring Music TheoryRygian
Scale 1517Scale 1517: Sagyllic, Ian Ring Music TheorySagyllic

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.