Sensi: Difference between revisions
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'''Sensi''' is a [[rank-2 temperament|rank-2]] [[regular temperament]] | '''Sensi''' is a [[rank-2 temperament|rank-2]] [[regular temperament]] that is [[generator|generated]] by an extremely sharp major third of between 442 and 445{{cent}}. In the [[7-limit]], this interval represents [[9/7]], and by the most important equivalence in sensi (i.e. [[tempering out]] [[245/243]]), two of these thirds stack to a major sixth which approximates [[5/3]]. The next comma to be tempered out is [[126/125]], through which three of these major sixths approximate [[7/6]], two octaves up. The [[6/1|6th harmonic]] is therefore split into seven. Furthermore, since the supermajor third is tempered so sharply, it makes sense to have it represent both 9/7 and [[13/10]], which results in [[91/90]] being tempered out in the 2.3.5.7.13 [[subgroup]]. | ||
Equal temperaments that support sensi include [[19edo]] (generator 7\19; [[soft]] [[checkertonic]]), [[27edo]] (generator 10\27; [[supersoft]] checkertonic), and [[46edo]] (generator 17\46; {{nowrap| L/s {{=}} 7/5 }}, more optimized for sensi temperament) | The structure whereby 5/3 is split into two supermajor thirds is obviously xenharmonic as this cannot occur in [[12edo]]. But particularly, as the simplest [[EDO]]s with similar structures are [[8edo]] and [[11edo]] (whence the 8-note and 11-note [[MOS scale]]s), sensi has a very xenmelodic character compared to many other ways of organizing the 7-limit (such as [[superpyth]], which is based on the familiar [[chain of fifths]], and even [[porcupine]], which is fundamentally heptatonic). | ||
Equal temperaments that support sensi include [[19edo]] (generator 7\19; [[soft]] [[checkertonic]]), [[27edo]] (generator 10\27; [[supersoft]] checkertonic), and [[46edo]] (generator 17\46; {{nowrap| L/s {{=}} 7/5 }}, more optimized for sensi temperament). | |||
See [[Sensipent family #Sensi]] for more technical data, and [[Sensi extensions]] for extensions of sensi that include the [[11/1|11th harmonic]]. | See [[Sensipent family #Sensi]] for more technical data, and [[Sensi extensions]] for extensions of sensi that include the [[11/1|11th harmonic]]. | ||
== | == Theory == | ||
=== Sensi vs. sentry vs. sensipent === | |||
{{Main| Sensipent }} | |||
It is worth noting that sensi distinguishes itself from other structures based around 245/243 (whose basic form in the 2.9/7.5/3 subgroup is known as [[sentry]]) by virtue of its minor third (6/5) being ''flattened'' from just rather than sharpened. This results in the supermajor third being sharpened even more than is typical, so much so that it is tuned [[interseptimal]]ly and may not fulfill all the functions that [[~]]9/7 is intended to have. | |||
One way around this is to eschew the generator's interpretation as 9/7 altogether, and focus on the [[5-limit]] part of sensi, which is known as [[sensipent]] (whose comma is [[78732/78125]]). From there, an interpretation of the generator as [[31/24]]~[[40/31]] is apparent. Beyond the 2.3.5.31 subgroup, more accurate interpretations (in comparison to sensi) of sensipent's extended harmony are given by [[sensible]] (adding primes 11, 17, and 23) and [[sendai]] (adding 23 and 29). | |||
=== Interval chain === | === Interval chain === | ||
In the following table, odd harmonics and subharmonics 1–21 are in '''bold'''. | In the following table, odd harmonics and subharmonics 1–21 are in '''bold'''. | ||
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<nowiki/>* In 2.3.5.7.13 CWE tuning | <nowiki/>* In 2.3.5.7.13 CWE tuning | ||
=== | === Intervals of Sensi[8] === | ||
Sensi[8] is a [[mos scale]] with a [[3L 5s]] pattern (or [[5L 3s]] in extreme cases where the generator is larger than 450{{c}}). See [[3L 5s #Modes]] (resp. [[5L 3s #Modes]]) to see which modes have which qualities for each interval size. | Sensi[8] is a [[mos scale]] with a [[3L 5s]] pattern (or [[5L 3s]] in extreme cases where the generator is larger than 450{{c}}). See [[3L 5s #Modes]] (resp. [[5L 3s #Modes]]) to see which modes have which qualities for each interval size. | ||