User:Ganaram inukshuk/TAMNAMS: Difference between revisions
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==Naming mos intervals== | ==Naming mos intervals== | ||
Mos intervals are | Mos intervals are named after the number of steps (large or small) they subtend. An interval that spans ''k'' mossteps is called a ''k-mosstep interval'', or simply a ''k-mosstep'' (abbreviated ''kms''). This can be further shortened to ''k-step'' if context allows. | ||
Generic mos intervals only denote how many mossteps an interval subtends. Mossteps are zero-indexed, counting the number of steps subtended rather than the number of scale degrees, meaning that the unison is called a ''0-mosstep'', since a unison has zero steps. A mosstep that reaches the octave is simply called the ''octave''. | |||
Specific mos intervals denote the sizes, or [[Interval variety|varieties]], an interval can be. Per the definition of a moment of symmetry scale (that is, [[maximum variety]] 2), every interval, except for the root and multiples of the period, has two sizes: large and small. The terms ''major'', ''minor'', ''augmented'', ''perfect'', and ''diminished'' are added before the phrase ''k-mosstep'' using the following rules: | |||
Specific mos intervals denote the sizes, or [[Interval variety|varieties]], an interval | |||
* Multiples of the period such as the root and octave are '''perfect''', as they only have one size each. | * Multiples of the period such as the root and octave are '''perfect''', as they only have one size each. | ||
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Additionally, the designations of augmented, perfect, and diminished don't apply for the generators for mosses of the form ''n''L ''n''s; instead, major and minor is used. This is to prevent ambiguity over calling every interval perfect. | Additionally, the designations of augmented, perfect, and diminished don't apply for the generators for mosses of the form ''n''L ''n''s; instead, major and minor is used. This is to prevent ambiguity over calling every interval perfect. | ||
Examples using 5L 2s and 4L 4s are provided below. Note that 5L 2s interval names are identical to that of standard music theory, apart from the 0-indexed interval names. For a detailed derivation of these intervals, see the appendix. | Examples using 5L 2s and 4L 4s are provided below. Note that 5L 2s interval names are identical to that of standard music theory, apart from the 0-indexed interval names. For a detailed derivation of these intervals, see the appendix. | ||
<table> | <table> | ||
<tr> | <tr> | ||
<td style="vertical-align:top">{{MOS intervals|Scale Signature=5L 2s}}</td> | <td style="vertical-align:top">{{MOS intervals|Scale Signature=5L 2s}}</td><td></td><td style="vertical-align:top">{{MOS intervals|Scale Signature=4L 4s}}</td> | ||
<td style="vertical-align:top">{{MOS intervals|Scale Signature=4L 4s}}</td> | |||
</tr> | </tr> | ||
</table> | </table> | ||
===Alterations by a chroma=== | ===Alterations by a chroma=== | ||
The terms ''augmented'' and ''diminished'' are also used to describe intervals that are further lowered or raised by a ''chroma'', a generalized sharp or flat. The rules for alteration are as follows: | |||
* Raising a minor interval by a chroma makes it minor. Lowering a major interval by a chroma makes it major. Thus, a chroma is the difference between a large and small step. | |||
* Raising a major interval by a chroma makes it augmented. | |||
* Lowering a minor interval by a chroma makes it diminished. | |||
* Raising an augmented interval by a chroma makes it doubly augmented. | |||
* Lowering a diminished interval by a chroma makes it doubly diminished. | |||
Repetition of "A" or "d" is used to denote repeatedly augmented/diminished | Repetition of "A" or "d" is used to denote repeatedly augmented/diminished intervals, and is sufficient in most cases. It's typically uncommon to alter an interval more than three times, and superscript numbers or alternate notation is advised. The table below shows how these would be notated. | ||
{| class="wikitable" | {| class="wikitable" | ||
|+Table of alterations, with abbreviations | |+Table of alterations, with abbreviations | ||
|- | |- | ||
!Number of chromas | !Number of chromas | ||
! | !Perfectable intervals | ||
! Major/minor intervals | ! Major/minor intervals | ||
|- | |- | ||
| +3 chromas | | +4 chromas | ||
|Triply-augmented (AAA, | |Quadruply-augmented (A<sup>4</sup> or A^4) | ||
|Triply-augmented (AAA, | |Quadruply-augmented (A<sup>4</sup> or A^4) | ||
|- | |||
| +3 chromas | |||
|Triply-augmented (AAA, A<sup>3</sup>, or A^3) | |||
|Triply-augmented (AAA, A<sup>3</sup>, or A^3) | |||
|- | |- | ||
| +2 chromas | | +2 chromas | ||
|Doubly-augmented (AA) | |Doubly-augmented (AA) | ||
|Doubly-augmented (AA) | |Doubly-augmented (AA) | ||
|- | |- | ||
| +1 chroma | | +1 chroma | ||
|Augmented (A) | |Augmented (A) | ||
|Augmented (A) | |Augmented (A) | ||
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|Minor (m) | |Minor (m) | ||
|- | |- | ||
| -1 chroma | | -1 chroma | ||
|Diminished (d) | |Diminished (d) | ||
|Diminished (d) | |Diminished (d) | ||
|- | |- | ||
| -2 chromas | | -2 chromas | ||
|Doubly-diminished (dd) | |Doubly-diminished (dd) | ||
|Doubly-diminished (dd) | |Doubly-diminished (dd) | ||
|- | |- | ||
| -3 chromas | | -3 chromas | ||
|Triply-diminished (ddd, | |Triply-diminished (ddd, d<sup>3</sup>, or d^3) | ||
|Triply-diminished (ddd, | |Triply-diminished (ddd, d<sup>3</sup>, or d^3) | ||
|- | |||
| -4 chromas | |||
|Quadruply-diminished (d<sup>4</sup> or d^4) | |||
|Quadruply-diminished (d<sup>4</sup> or d^4) | |||
|} | |} | ||
===Naming neutral and interordinal intervals=== | ===Naming neutral and interordinal intervals=== |