256/255: Difference between revisions

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added missing temperament information following clean up of related temperaments and applied rename following mentioned rename conventions
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{{Infobox Interval
{{Infobox Interval
| Name = septendecimal kleisma, <br>char(i)sma, <br>diasemisma, <br>255th subharmonic
| Name = septendecimal kleisma, <br>charisma, <br>255th subharmonic
| Color name = 17ug1, sugu 1sn, <br>Sugu comma
| Color name = 17ug1, sugu 1sn, <br>Sugu comma
| Comma = yes
| Comma = yes
}}
}}


'''256/255''', the '''septendecimal kleisma''', '''char(i)sma''', '''diasemisma''' or '''255th subharmonic''' is a [[small comma|small]] [[17-limit]] [[superparticular]] comma about 6.8 [[cent]]s in size. It is the difference between [[16/15]] (classical diatonic semitone) and [[17/16]] (large septendecimal semitone, also called as ''minor diatonic semitone''), and forms the amount by which a stack consisting of [[15/8]] and 17/16 falls short of an [[octave]]. It differs from [[352/351]] (the minthma) by [[936/935]] – an [[unnoticeable comma]] measuring about 1.85 cents.
'''256/255''', the '''septendecimal kleisma''', '''charisma''' or '''255th subharmonic''' is a [[small comma|small]] [[17-limit]] [[superparticular]] comma about 6.8 [[cent]]s in size. It is the difference between [[16/15]] (the classical diatonic semitone) and [[17/16]] (the large septendecimal semitone) and forms the amount by which a stack consisting of [[15/8]] and 17/16 falls short of an [[octave]]. It differs from [[352/351]] (the minthma) by [[936/935]] – an [[unnoticeable comma]] measuring about 1.85 cents.


By tempering it out is defined the '''char(i)smic temperament''' (full 17-limit rank-6) or '''charic temperament''' (2.3.5.17 subgroup rank-3), which enables the [[diasemismic chords|char(i)smic chords]].
== Temperaments ==
By tempering it out is defined the '''charismic temperament''' (full 17-limit rank-6) or '''charic temperament''' (2.3.5.17 subgroup rank-3), which enables the [[charismic chords]].
=== Charic ===
[[Subgroup]]: 2.3.5.17


== Etymology ==
Patent EDO tunings with [[relative error]] < 1/3 for all generators: 3, 9, 10, 12, 15, 21, 22, 24, 31, 32, 34, 43, 44, 46, 55, 56, 58, 65, 68, 77, 80, 111, 114, 145
The name ''diasemisma'' was named by [[User:Xenllium|Xenllium]] in May 2023. It is a contraction of ''diatonic semitone'' into a single word; it is unrelated to the [[diasem]] scale structure. However, ''septendecimal kleisma'' and ''255th subharmonic'' were attested much earlier.


Starshine (from the [[XA Discord]] server) suggested (half-jokingly) that a chance had been missed to name it the ''charisma'' in December 2023, a name which [[User:Godtone|Godtone]] took favor to and championed. A revision to ''charsma'' (no-''i'' spelling) was proposed by Xenllium in January 2024 for disambiguation (formerly ''charisma'' and ''charismic'' were used for [[Magic family #Horcrux|horcrux extensions]]); the only issue taken with this is its inconsistency with the -ic -ismic -isma rule and that the temperaments were already suggested to be renamed in the proposal by Godtone for this and other reasons. The "char" in the name "charisma" refers to the char data type in C-derived programming languages, where the char represents a byte of at least or exactly 8 bits. Thereby, the maximum unsigned value for an 8-bit char is 255 and the number of values an 8-bit char can take is 256, hence [[256/255]].
[[CTE]] generators: (2/1,) 3/2 = 702.647, 5/4 = 387.798
 
=== Charismic ===
[[Subgroup]]: [[17-limit]]
 
Patent EDO tunings with [[relative error]] < 1/3 for all generators: 9, 31, 43, 46, 56
 
[[CTE]] generators: [same as charic plus pure extra primes]
 
=== [[Srutal archagall]] ===
By also tempering the [[semitonisma]], [[256/255]], an efficient temperament known as [[Srutal archagall]] is achieved, which is equivalently described as [[charic]] [[semitonic]].
 
This is because of a general fact of [[S-expression]]s; in this case it manifests as that: {[[diaschisma|S16<sup>2</sup> × S17]] , [[24576/24565|S16/S17]]} = {[[256/255|S16]], [[289/288|S17]]}
 
== Etymology and history ==
The "char" in the name "charisma" refers to the char data type in C-derived programming languages, where the char represents a byte of at least or exactly 8 bits. Thereby, the maximum unsigned value for an 8-bit char is 255 and the number of values an 8-bit char can take is 256, hence [[256/255]].
 
The former name ''diasemisma'' was proposed by [[User:Xenllium|Xenllium]] in May 2023. It is a contraction of ''diatonic semitone'' into a single word, however, a rename to [[charisma]] was proposed as part of an effort to make naming more standardised and for a number of reasons including potential confusion with [[diasem]] and the former nonconforming naming of [[horcrux]] in the 11- and 13-limit (which were formerly named "charisma" and "charismic", creating a potential false impression that the former was a comma, not a temperament, and that the latter was the temperament defined by tempering that comma in the corresponding prime limit); specifically, see [[Talk:256/255]] and [[Temperament_naming#Contemporary_rules]] for details.
 
The rename took place as Starshine (from the [[XA Discord]] server) suggested (half-jokingly) that a chance had been missed to name it the ''charisma'' in December 2023, a name which [[User:Godtone|Godtone]] took favor to and championed which then caused awareness of nonconforming names of two [[horcrux]] temeraments. A revision to ''charsma'' (no-''i'' spelling) was proposed by Xenllium in January 2024 for disambiguation but this would cause inconsistency with the -ic -ismic -isma rule which is a reason that those same temperaments were already being proposed to be renamed.


== See also ==
== See also ==
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* [[List of superparticular intervals]]
* [[List of superparticular intervals]]


[[Category:Charsmic]]
[[Category:Charismic]]