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Scale 3605: "Olkian"

Scale 3605: Olkian, 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




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


Forte Number

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


Rotational Symmetry

Some scales have rotational symmetry, sometimes known as "limited transposition". If there are any rotational symmetries, these are the intervals of periodicity.


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.



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



A chiral scale can not be transformed into its inverse by rotation. If a scale is chiral, then it has an enantiomorph.

enantiomorph: 1295


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

3 (trihemitonic)


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

2 (dicohemitonic)


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.



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.


Prime Form

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

prime: 175


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


Deep Scale

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


Interval Structure

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

[2, 2, 5, 1, 1, 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.

<3, 4, 2, 2, 3, 1>

Interval Spectrum

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


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

Spectra Variation

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


Maximally Even

A scale is maximally even if the tones are optimally spaced apart from each other.


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.


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.


Polygon Perimeter

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


Myhill Property

A scale has Myhill Property if the Interval Spectra has exactly two specific intervals for every generic interval.



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.


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.



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".


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.

(29, 19, 65)

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
Minor Triadsam{9,0,4}000

The following pitch classes are not present in any of the common triads: {2,10,11}

Since there is only one common triad in this scale, there are no opportunities for parsimonious voice leading between triads.


Modes are the rotational transformation of this scale. Scale 3605 can be rotated to make 5 other scales. The 1st mode is itself.

2nd mode:
Scale 1925
Scale 1925: Lumian, Ian Ring Music TheoryLumian
3rd mode:
Scale 1505
Scale 1505: Jepian, Ian Ring Music TheoryJepian
4th mode:
Scale 175
Scale 175: Bewian, Ian Ring Music TheoryBewianThis is the prime mode
5th mode:
Scale 2135
Scale 2135: Nakian, Ian Ring Music TheoryNakian
6th mode:
Scale 3115
Scale 3115: Tihian, Ian Ring Music TheoryTihian


The prime form of this scale is Scale 175

Scale 175Scale 175: Bewian, Ian Ring Music TheoryBewian


The hexatonic modal family [3605, 1925, 1505, 175, 2135, 3115] (Forte: 6-9) is the complement of the hexatonic modal family [175, 1505, 1925, 2135, 3115, 3605] (Forte: 6-9)


The inverse of a scale is a reflection using the root as its axis. The inverse of 3605 is 1295

Scale 1295Scale 1295: Huyian, Ian Ring Music TheoryHuyian


Only scales that are chiral will have an enantiomorph. Scale 3605 is chiral, and its enantiomorph is scale 1295

Scale 1295Scale 1295: Huyian, Ian Ring Music TheoryHuyian


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> 3605       T0I <11,0> 1295
T1 <1,1> 3115      T1I <11,1> 2590
T2 <1,2> 2135      T2I <11,2> 1085
T3 <1,3> 175      T3I <11,3> 2170
T4 <1,4> 350      T4I <11,4> 245
T5 <1,5> 700      T5I <11,5> 490
T6 <1,6> 1400      T6I <11,6> 980
T7 <1,7> 2800      T7I <11,7> 1960
T8 <1,8> 1505      T8I <11,8> 3920
T9 <1,9> 3010      T9I <11,9> 3745
T10 <1,10> 1925      T10I <11,10> 3395
T11 <1,11> 3850      T11I <11,11> 2695
Abbrev Operation Result Abbrev Operation Result
T0M <5,0> 1925      T0MI <7,0> 1085
T1M <5,1> 3850      T1MI <7,1> 2170
T2M <5,2> 3605       T2MI <7,2> 245
T3M <5,3> 3115      T3MI <7,3> 490
T4M <5,4> 2135      T4MI <7,4> 980
T5M <5,5> 175      T5MI <7,5> 1960
T6M <5,6> 350      T6MI <7,6> 3920
T7M <5,7> 700      T7MI <7,7> 3745
T8M <5,8> 1400      T8MI <7,8> 3395
T9M <5,9> 2800      T9MI <7,9> 2695
T10M <5,10> 1505      T10MI <7,10> 1295
T11M <5,11> 3010      T11MI <7,11> 2590

The transformations that map this set to itself are: T0, T2M

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 3607Scale 3607: Wopian, Ian Ring Music TheoryWopian
Scale 3601Scale 3601: Wilian, Ian Ring Music TheoryWilian
Scale 3603Scale 3603: Womian, Ian Ring Music TheoryWomian
Scale 3609Scale 3609: Woqian, Ian Ring Music TheoryWoqian
Scale 3613Scale 3613: Wosian, Ian Ring Music TheoryWosian
Scale 3589Scale 3589: Widian, Ian Ring Music TheoryWidian
Scale 3597Scale 3597: Wijian, Ian Ring Music TheoryWijian
Scale 3621Scale 3621: Gylimic, Ian Ring Music TheoryGylimic
Scale 3637Scale 3637: Raga Rageshri, Ian Ring Music TheoryRaga Rageshri
Scale 3669Scale 3669: Mothian, Ian Ring Music TheoryMothian
Scale 3733Scale 3733: Gycrian, Ian Ring Music TheoryGycrian
Scale 3861Scale 3861: Phroptian, Ian Ring Music TheoryPhroptian
Scale 3093Scale 3093: Buqian, Ian Ring Music TheoryBuqian
Scale 3349Scale 3349: Aeolocrimic, Ian Ring Music TheoryAeolocrimic
Scale 2581Scale 2581: Raga Neroshta, Ian Ring Music TheoryRaga Neroshta
Scale 1557Scale 1557: Jovian, Ian Ring Music TheoryJovian

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 ( 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.