50/49: Difference between revisions

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**Imported revision 244873375 - Original comment: **
 
+ etymology
 
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<h2>IMPORTED REVISION FROM WIKISPACES</h2>
{{Interwiki
This is an imported revision from Wikispaces. The revision metadata is included below for reference:<br>
| en = 50/49
: This revision was by author [[User:genewardsmith|genewardsmith]] and made on <tt>2011-08-08 14:29:18 UTC</tt>.<br>
| de = 50/49
: The original revision id was <tt>244873375</tt>.<br>
| es =
: The revision comment was: <tt></tt><br>
| ja =
The revision contents are below, presented both in the original Wikispaces Wikitext format, and in HTML exactly as Wikispaces rendered it.<br>
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<h4>Original Wikitext content:</h4>
{{Infobox Interval
<div style="width:100%; max-height:400pt; overflow:auto; background-color:#f8f9fa; border: 1px solid #eaecf0; padding:0em"><pre style="margin:0px;border:none;background:none;word-wrap:break-word;white-space: pre-wrap ! important" class="old-revision-html">[[http://en.wikipedia.org/wiki/Septimal_sixth-tone]]</pre></div>
| Name = small septimal diesis, small septimal sixth-tone, septimal tritonic diesis, jubilisma
<h4>Original HTML content:</h4>
| Color name = rryy-2, biruyo negative 2nd,<br>Biruyo comma
<div style="width:100%; max-height:400pt; overflow:auto; background-color:#f8f9fa; border: 1px solid #eaecf0; padding:0em"><pre style="margin:0px;border:none;background:none;word-wrap:break-word;width:200%;white-space: pre-wrap ! important" class="old-revision-html">&lt;html&gt;&lt;head&gt;&lt;title&gt;50_49&lt;/title&gt;&lt;/head&gt;&lt;body&gt;&lt;a class="wiki_link_ext" href="http://en.wikipedia.org/wiki/Septimal_sixth-tone" rel="nofollow"&gt;http://en.wikipedia.org/wiki/Septimal_sixth-tone&lt;/a&gt;&lt;/body&gt;&lt;/html&gt;</pre></div>
| Comma = yes
}}
{{Wikipedia|Septimal third tone #Septimal sixth tone}}
 
'''50/49''', the '''small septimal diesis''' (a.k.a. '''small septimal sixth-tone''' or '''septimal tritonic diesis'''), is a [[7-limit]] [[medium comma]]. It is the only [[superparticular]] [[comma]] in the 7-limit aside from [[126/125]] and [[4375/4374]] which has a numerator which is neither square nor [[triangular number|triangular]], meaning it is not the difference between septimal superparticular rations with numerators differing by either one or two; instead, {{nowrap| 50/49 = ([[10/7]])/([[7/5]]) }}.  
 
== Temperaments ==
[[Tempering out]] this comma equates the two septimal tritones (i.e. [[7/5]] and [[10/7]]) with each other, leading to temperaments where [[sqrt(2/1)]] approximates both. In the [[2.5.7 subgroup]], this is known as the jubilic temperament, and the comma is thus known as the '''jubilisma'''. In the full 7-limit, this comma further equates [[15/14]] and [[21/20]] and enables all the [[jubilismic chords]].  
 
''It cannot be tempered out if all of the consonances of the 7-odd-limit are distinct'', but it ''can'' be equated with other commas; for example:
* ([[36/35]])/(50/49) = [[126/125]]
* ([[45/44]])/(50/49) = [[441/440]]
* ([[49/48]])/(50/49) = [[2401/2400]]
* (50/49)/([[55/54]]) = [[540/539]]
* (50/49)/([[56/55]]) = [[1375/1372]]
* (50/49)/([[64/63]]) = [[225/224]]
* (50/49)/([[65/64]]) = [[640/637]]
* (50/49)/([[66/65]]) = [[1625/1617]]
* (50/49)/([[78/77]]) = [[275/273]]
* (50/49)/([[81/80]]) = [[4000/3969]]
 
See [[Jubilismic family]] for the rank-3 family where it is tempered out, and [[Jubilismic clan]] for the rank-2 clan where it is tempered out.
 
Equal temperaments tempering out 50/49 include [[12edo]], [[22edo]], [[26edo]], [[38edo]], [[48edo]], and [[54edo]].
 
== Approximations ==
{{Interval edo approximation|min_edo=12}}
 
== Etymology ==
The name ''jubilisma'' is likely a reference to the 50-year biblical jubilee cycle.  
 
== See also ==
* [[List of superparticular intervals]]
* [[49/48]] – the large septimal sixth-tone
 
[[Category:Jubilismic]]
[[Category:Commas referencing a famous use of a number]]