55/54: Difference between revisions

BudjarnLambeth (talk | contribs)
Less detail about 432hz. We can include all that in a 432 Hz article if anyone is ever masochistic enough to make one.
Overthink (talk | contribs)
temperaments section
 
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'''55/54''', the '''telepathma''', otherwise known as the '''undecimal diasecundal comma''' or the '''eleventyfive comma''', is an [[11-limit]] [[superparticular]] interval that marks the difference between the classic minor third ([[6/5]]) and the undecimal neutral third ([[11/9]]), between the classic major third ([[5/4]]) and the rastmic neutral third ([[27/22]]), as well as the difference between the keenanismic supermajor sixth ([[55/32]]) and the Pythagorean major sixth ([[27/16]]). This means that 6/5 and 11/9 are equated – as are 55/32 and 27/16 – when this comma is tempered out. [[EDO]]s that temper out this interval include {{EDOs| 5, 7, 8, 10, 15, 17, 22, 27, 29, 30, 32, 37, 42, 44, 51, 54, 59 and 66}}.
'''55/54''', the '''telepathma''', otherwise known as the '''undecimal diasecundal comma''' or the '''eleventyfive comma''', is an [[11-limit]] [[superparticular]] interval that marks the difference between the classic minor third ([[6/5]]) and the undecimal neutral third ([[11/9]]), between the classic major third ([[5/4]]) and the rastmic neutral third ([[27/22]]), between the minor whole tone ([[10/9]]) and the lesser undecimal neutral second ([[12/11]]), as well as the difference between the keenanismic supermajor sixth ([[55/32]]) and the Pythagorean major sixth ([[27/16]]).


When treated as an interval in its own right, it acts as a sort of parachroma in much the same fashion as [[33/32]], from which it differs by a [[81/80|syntonic comma]].  However, given that it's noticeably smaller in size than 33/32, one can also easily use it in melodies as either an [[Wikipedia:Appoggiatura|appoggiatura]], an [[Wikipedia:Acciaccatura|acciaccatura]], or a quick passing tone. Tempering out the lehmerisma ([[3025/3024]]) equates this interval with [[56/55]], splitting the [[28/27]] septimal chroma into two equal halves.  Furthermore, when the [[385/384|keenanisma]] is tempered out, 55/54 is equated with [[64/63]], and it is partially on this basis that one can reasonably make the argument that 64/63 can act as the septimal equivalent for 55/54.
When treated as an interval in its own right, it acts as a sort of parachroma in much the same fashion as [[33/32]], from which it differs by a [[81/80|syntonic comma]].  However, given that it's noticeably smaller in size than 33/32, one can also easily use it in melodies as either an [[Wikipedia:Appoggiatura|appoggiatura]], an [[Wikipedia:Acciaccatura|acciaccatura]], or a quick passing tone. Tempering out the lehmerisma ([[3025/3024]]) equates this interval with [[56/55]], splitting the [[28/27]] septimal chroma into two equal halves.  Furthermore, when the [[385/384|keenanisma]] is tempered out, 55/54 is equated with [[64/63]], and it is partially on this basis that one can reasonably make the argument that 64/63 can act as the septimal equivalent for 55/54.


It is also the difference between the universally accepted 440 Hz pitch standard and the esoteric 432 Hz pitch standard.
It is also the difference between the universally accepted 440 Hz pitch standard and the esoteric 432 Hz pitch standard.
== Temperaments ==
Tempering out this comma means that 6/5 and 11/9 are equated, as are 55/32 and 27/16. [[Edo]]s that temper out this interval by patent val include {{EDOs| 5, 7, 8, 10, 15, 17, 22, 27, 29, 30, 32, 37, 42, 44, 51, 54, 59 and 66}}. Since tempering out 55/54 equates 10/9 with 12/11, it is natural to equate both with [[11/10]] as well (tempering out [[100/99]] and [[121/120]]), leading to the [[2.3.5.11 subgroup|2.3.5.11-subgroup]] version of [[porcupine]] temperament. Additionally, tempering out 55/54 requires tuning the [[3/2|perfect fifth]] sharply to maintain accuracy, meaning it is natural to temper out 64/63 as well, finding [[7/4]] at two perfect fourths, extending porcupine to the full 11-limit. Other extensions of porcupine to prime 7 are detailed in the [[porcupine family]].
Non-porcupine temperaments that temper out 55/54 include [[telepathy]], [[intuition]], [[pajarous]], [[darjeeling]], [[suprapyth]], [[fleetwood]], and [[negroni]].


== Sagittal notation ==
== Sagittal notation ==