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Scale 1505: "Jepian"

Scale 1505: Jepian, 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

Dozenal
Jepian

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

{0,5,6,7,8,10}

Forte Number

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

6-9

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.

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: 245

Hemitonia

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

3 (trihemitonic)

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.

5

Prime Form

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

no
prime: 175

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.

[5, 1, 1, 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.

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

Interval Spectrum

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

p3m2n2s4d3t

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.

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.

1.866

Polygon Perimeter

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

5.485

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.

(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 Triadsfm{5,8,0}000

The following pitch classes are not present in any of the common triads: {6,7,10}

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

Modes

Modes are the rotational transformation of this scale. Scale 1505 can be rotated to make 5 other scales. The 1st mode is itself.

2nd mode:
Scale 175
Scale 175: Bewian, Ian Ring Music TheoryBewianThis is the prime mode
3rd mode:
Scale 2135
Scale 2135: Nakian, Ian Ring Music TheoryNakian
4th mode:
Scale 3115
Scale 3115: Tihian, Ian Ring Music TheoryTihian
5th mode:
Scale 3605
Scale 3605: Olkian, Ian Ring Music TheoryOlkian
6th mode:
Scale 1925
Scale 1925: Lumian, Ian Ring Music TheoryLumian

Prime

The prime form of this scale is Scale 175

Scale 175Scale 175: Bewian, Ian Ring Music TheoryBewian

Complement

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

Inverse

The inverse of a scale is a reflection using the root as its axis. The inverse of 1505 is 245

Scale 245Scale 245: Raga Dipak, Ian Ring Music TheoryRaga Dipak

Enantiomorph

Only scales that are chiral will have an enantiomorph. Scale 1505 is chiral, and its enantiomorph is scale 245

Scale 245Scale 245: Raga Dipak, Ian Ring Music TheoryRaga Dipak

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

The transformations that map this set to itself are: T0, T6M

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 1507Scale 1507: Zynian, Ian Ring Music TheoryZynian
Scale 1509Scale 1509: Ragian, Ian Ring Music TheoryRagian
Scale 1513Scale 1513: Stathian, Ian Ring Music TheoryStathian
Scale 1521Scale 1521: Stanian, Ian Ring Music TheoryStanian
Scale 1473Scale 1473: Javian, Ian Ring Music TheoryJavian
Scale 1489Scale 1489: Raga Jyoti, Ian Ring Music TheoryRaga Jyoti
Scale 1441Scale 1441: Jabian, Ian Ring Music TheoryJabian
Scale 1377Scale 1377: Insian, Ian Ring Music TheoryInsian
Scale 1249Scale 1249: Howian, Ian Ring Music TheoryHowian
Scale 1761Scale 1761: Kuqian, Ian Ring Music TheoryKuqian
Scale 2017Scale 2017: Meqian, Ian Ring Music TheoryMeqian
Scale 481Scale 481: Dabian, Ian Ring Music TheoryDabian
Scale 993Scale 993: Gavian, Ian Ring Music TheoryGavian
Scale 2529Scale 2529: Pikian, Ian Ring Music TheoryPikian
Scale 3553Scale 3553: Wehian, Ian Ring Music TheoryWehian

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.