31edo: Difference between revisions

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Wikispaces>hstraub
**Imported revision 15116587 - Original comment: 31EDO interval naming sheme added. Broken link removed.**
Wikispaces>xenjacob
**Imported revision 37988910 - Original comment: **
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<h2>IMPORTED REVISION FROM WIKISPACES</h2>
<h2>IMPORTED REVISION FROM WIKISPACES</h2>
This is an imported revision from Wikispaces. The revision metadata is included below for reference:<br>
This is an imported revision from Wikispaces. The revision metadata is included below for reference:<br>
: This revision was by author [[User:hstraub|hstraub]] and made on <tt>2008-01-21 10:07:09 UTC</tt>.<br>
: This revision was by author [[User:xenjacob|xenjacob]] and made on <tt>2008-09-12 15:10:36 UTC</tt>.<br>
: The original revision id was <tt>15116587</tt>.<br>
: The original revision id was <tt>37988910</tt>.<br>
: The revision comment was: <tt>31EDO interval naming sheme added. Broken link removed.</tt><br>
: The revision comment was: <tt></tt><br>
The revision contents are below, presented both in the original Wikispaces Wikitext format, and in HTML exactly as Wikispaces rendered it.<br>
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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<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">[[toc|flat]]
<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">[[toc|flat]]


----
//Thirty-one tone equal temperament//, also called //31-tET//, //31-EDO//, //31-et//, or //tricesimoprimal temperament//, is the scale derived by dividing the octave into 31 [[equal|equally]] large steps. Each step is equivalent to a frequency ratio of the 31st root of 2, or 38.71 [[cents]].
For more encyclopedic info, see [[http://en.wikipedia.org/wiki/31_equal_temperament|Wikipedia's article]].
=Intervals=
===Diesis - 1/31 octave===
A single step of 31-edo is about 38.7¢. Intervals around this size are called [[diesis|dieses]] (singular 'diesis'). In 31 it is equivalent to the difference between one octave and three stacked major thirds (C to E, to G#, to B#, but B# ≠ C), or four minor thirds (C to Eb to Gb to Bbb to Dbb ≠ C). Demonstrated in [[SpiralProgressions]].
===2/31 octave===
The difference between a major and minor third. The more 'expressive' of the 'half steps'.
===3/31 octave===
The difference between a perfect fourth and a major third. The larger and clunkier of the 'half steps'.
===Neutral second - 4/31 octave===
Exactly one half of the minor third.


----
===5/31 octave===
In music, '''31 equal temperament''', called 31-tet, 31-edo, 31-et, or tricesimoprimal temperament, is the scale derived by dividing the octave into 31 equally large steps. Each step represents a frequency ratio of the 31st root of 2, or 38.71 cents.
A rather smallish whole tone. Often called melodically dull.
 
===6/31 octave===
A 'supermajor 2nd'.
 
===7/31 octave===
A 'subminor 3rd'.
 
===8/31 octave===
A minor third, closer to the just 6:5 than 12-edo, but not really close enough.
 
===9/31 octave===
A neutral 3rd, practically equivalent to 11:9.
 
===10/31 octave===
A near-just major 3rd. Has led to the characterization of 31-edo as "smooth".
 
===11/31 octave===
A 'supermajor 3rd'.
 
===12/31 octave===
A narrow fourth.
 
===13/31 octave===
Not very satisfying.
 
===14/31 octave===
10¢ off from a just 11:8; barely functional as such.
 
===15/31 octave===
The small tritone.


Nicola Vicentino had very nearly produced 31-equal temperament on his extended keyboard instrument, the Archicembalo, in 1555, but it was not until 1666 that Lemme Rossi first proposed it theoretically. Shortly thereafter, having discovered it independently, famed scientist Christiaan Huygens wrote about it also. Since the standard system of tuning at that time was quarter-comma meantone, in which the fifth is tuned to the fourth root of 5, the appeal of this method is immediate, as the fifth of 31-et, at 696.77 cents, is only a fifth of a cent sharper than the fifth of quarter-comma meantone. Huygens not only realized that, he went farther and noted that 31-et provides an excellent approximation of septimal, or 7-limit harmony, which was a very advanced insight for the time. In the twentieth century, physicist, music theorist and composer Adriaan Fokker, after reading Huygens's work, led a revival of interest in this system of tuning which led to a number of compositions, particularly by Dutch composers.
===16/31 octave===
The large tritone.


=Theoretical properties=  
===17/31 octave===
===18/31 octave===
===19/31 octave===
===20/31 octave===
===21/31 octave===
===22/31 octave===
===23/31 octave===
===24/31 octave===
===25/31 octave===
===26/31 octave===
===27/31 octave===
===28/31 octave===
===29/31 octave===
===30/31 octave===
===perfect octave - 31/31 octave===  


The single most important fact about 31-et is that it equates to the unison, or ''tempers out'', the syntonic comma of 81/80. It is therefore a meantone temperament. It also tempers the 5-limit intervals 393216/390625, known as the Würschmidt comma after music theorist José Würschmidt, and 2109375/2097152, known as the semicomma.


More significantly, perhaps, it tempers out 126/125, the septimal semicomma, or starling comma. Because it tempers out both 81/80 and 126/125, it supports septimal meantone temperament. It also tempers out 1029/1024, the gamelan residue, and 1728/1715, the orwell comma. Consequently it supports a wide variety of [[http://xenharmonic.wikispaces.com/Regular+Temperaments#lineartemperaments|linear temperaments]].
=Modes=
When 31 is too many alternatives to choose from.


==Chords of 31 equal temperament==
A large open list of modes (subsets) from 31-edo that people have named: [[31edo modes]]. Some of the popular ones:


Many of the most interesting chords of 31-et are those of septimal meantone temperament. Others are the neutral thirds triad, which might be written either C-Dx-G or C-Fbb-G, and the orwell tetrad, which is C-E-Fx-Bbb.
* 31-tone major: 5 5 3 5 5 5 3
* 1/4-comma meantone (Eb-G#): 2 3 3 2 3 2 3 2 3 3 2 3
* Harmonic scale 8: 5 5 4 4 4 4 3 3
* the [[Euler-fokker genera]] (technically [[JI]] but representable in 31)


=Scales=  
=Music in 31-edo=  
[[31-edo compositions|An alphabetical list of Tricesimoprimal Compositions]].


[[shortspeak|31EDO interval naming scheme]]
==Thirty-one tone pedagogy==
The [[MicroPedagogyCollective]] is currently at work producing demonstrative material which will encourage and enable more people to learn this system. There have been two [[ThirtyOneToneSinginCamp]]s as well.


==Septatonic tetrachordal scales==
[[31edo Tetra 5-3-5]] [[31edo Tetra 5-4-4]] [[31edo Tetra 5-5-3]] [[31edo Tetra 5-6-2]] [[31edo Tetra 5-7-1]]
[[31edo Tetra 6-1-6]] [[31edo Tetra 6-2-5]] [[31edo Tetra 6-3-4]] [[31edo Tetra 6-4-3]] [[31edo Tetra 6-5-2]] [[31edo Tetra 6-6-1]]
[[31edo Tetra 7-1-5]] [[31edo Tetra 7-2-4]] [[31edo Tetra 7-3-3]] [[31edo Tetra 7-4-2]] [[31edo Tetra 7-5-1]]
[[31edo Tetra 8-1-4]] [[31edo Tetra 8-2-3]] [[31edo Tetra 8-4-1]]
[[31edo Tetra 9-1-3]] [[31edo Tetra 9-2-2]] [[31edo Tetra 9-3-1]]
[[31edo Tetra 10-1-2]] [[31edo Tetra 10-2-1]] [[31edo Tetra 11-1-1]]


=External links=  
=Other Articles=  
* [[[http://www.xs4all.nl/%7Ehuygensf/english/index.html|http://www.xs4all.nl/~huygensf/english/index.html]] de Beer, Anton, ''The Development of 31-tone Music'']
* [&lt;span class="wiki_link_ext"&gt;[http://www.xs4all.nl/~huygensf/english/index.html&lt;/span&gt;|de Beer, Anton, ''The Development of 31-tone Music'']]
* [[[http://www.xs4all.nl/%7Ehuygensf/doc/fokkerorg.html|http://www.xs4all.nl/~huygensf/doc/fokkerorg.html]] Fokker, Adriaan Daniël, ''Equal Temperament and the Thirty-one-keyed organ'']
* [[&lt;span class="wiki_link_ext"&gt;http://www.xs4all.nl/~huygensf/doc/fokkerorg.html&lt;/span&gt;|Fokker, Adriaan Daniël, ''Equal Temperament and the Thirty-one-keyed organ'']]
* [[[http://www.xs4all.nl/%7Ehuygensf/doc/rap31.html|http://www.xs4all.nl/~huygensf/doc/rap31.html]] Rapoport, Paul, ''About 31-tone Equal Temperament'']
* Fokker, A.D., "New Music with 31 Notes" translated by Leigh Gerdine
* [[[http://www.xs4all.nl/%7Ehuygensf/doc/terp31.html|http://www.xs4all.nl/~huygensf/doc/terp31.html]] Terpstra, Siemen, ''Toward a Theory of Meantone (and 31-et) Harmony'']
* [[&lt;span class="wiki_link_ext"&gt;http://www.xs4all.nl/~huygensf/doc/rap31.html&lt;/span&gt;|Rapoport, Paul, ''About 31-tone Equal Temperament'']
* [http://tonalsoft.com/enc/number/31edo.aspx Tonalsoft Encyclopedia of Microtonal Music-theory]</pre></div>
* [[&lt;span class="wiki_link_ext"&gt;http://www.xs4all.nl/~huygensf/doc/terp31.html&lt;/span&gt;|Terpstra, Siemen, ''Toward a Theory of Meantone (and 31-et) Harmony'']]
* [[&lt;span class="wiki_link_ext"&gt;http://tonalsoft.com/enc/number/31edo.aspx&lt;/span&gt;|Tonalsoft Encyclopedia article]</pre></div>
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&lt;em&gt;Thirty-one tone equal temperament&lt;/em&gt;, also called &lt;em&gt;31-tET&lt;/em&gt;, &lt;em&gt;31-EDO&lt;/em&gt;, &lt;em&gt;31-et&lt;/em&gt;, or &lt;em&gt;tricesimoprimal temperament&lt;/em&gt;, is the scale derived by dividing the octave into 31 &lt;a class="wiki_link" href="/equal"&gt;equally&lt;/a&gt; large steps. Each step is equivalent to a frequency ratio of the 31st root of 2, or 38.71 &lt;a class="wiki_link" href="/cents"&gt;cents&lt;/a&gt;.&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
&lt;hr /&gt;
For more encyclopedic info, see &lt;a class="wiki_link_ext" href="http://en.wikipedia.org/wiki/31_equal_temperament" rel="nofollow"&gt;Wikipedia's article&lt;/a&gt;.&lt;br /&gt;
In music, '''31 equal temperament''', called 31-tet, 31-edo, 31-et, or tricesimoprimal temperament, is the scale derived by dividing the octave into 31 equally large steps. Each step represents a frequency ratio of the 31st root of 2, or 38.71 cents.&lt;br /&gt;
&lt;br /&gt;
&lt;!-- ws:start:WikiTextHeadingRule:0:&amp;lt;h1&amp;gt; --&gt;&lt;h1 id="toc0"&gt;&lt;a name="Intervals"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:0 --&gt;Intervals&lt;/h1&gt;
&lt;!-- ws:start:WikiTextHeadingRule:2:&amp;lt;h3&amp;gt; --&gt;&lt;h3 id="toc1"&gt;&lt;a name="Intervals--Diesis - 1/31 octave"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:2 --&gt;Diesis - 1/31 octave&lt;/h3&gt;
A single step of 31-edo is about 38.7¢. Intervals around this size are called &lt;a class="wiki_link" href="/diesis"&gt;dieses&lt;/a&gt; (singular 'diesis'). In 31 it is equivalent to the difference between one octave and three stacked major thirds (C to E, to G#, to B#, but B# ≠ C), or four minor thirds (C to Eb to Gb to Bbb to Dbb ≠ C). Demonstrated in &lt;a class="wiki_link" href="/SpiralProgressions"&gt;SpiralProgressions&lt;/a&gt;.&lt;br /&gt;
&lt;br /&gt;
&lt;!-- ws:start:WikiTextHeadingRule:4:&amp;lt;h3&amp;gt; --&gt;&lt;h3 id="toc2"&gt;&lt;a name="Intervals--2/31 octave"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:4 --&gt;2/31 octave&lt;/h3&gt;
The difference between a major and minor third. The more 'expressive' of the 'half steps'.&lt;br /&gt;
&lt;br /&gt;
&lt;!-- ws:start:WikiTextHeadingRule:6:&amp;lt;h3&amp;gt; --&gt;&lt;h3 id="toc3"&gt;&lt;a name="Intervals--3/31 octave"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:6 --&gt;3/31 octave&lt;/h3&gt;
The difference between a perfect fourth and a major third. The larger and clunkier of the 'half steps'.&lt;br /&gt;
&lt;br /&gt;
&lt;!-- ws:start:WikiTextHeadingRule:8:&amp;lt;h3&amp;gt; --&gt;&lt;h3 id="toc4"&gt;&lt;a name="Intervals--Neutral second - 4/31 octave"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:8 --&gt;Neutral second - 4/31 octave&lt;/h3&gt;
Exactly one half of the minor third.&lt;br /&gt;
&lt;br /&gt;
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A rather smallish whole tone. Often called melodically dull.&lt;br /&gt;
&lt;br /&gt;
&lt;!-- ws:start:WikiTextHeadingRule:12:&amp;lt;h3&amp;gt; --&gt;&lt;h3 id="toc6"&gt;&lt;a name="Intervals--6/31 octave"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:12 --&gt;6/31 octave&lt;/h3&gt;
A 'supermajor 2nd'.&lt;br /&gt;
&lt;br /&gt;
&lt;!-- ws:start:WikiTextHeadingRule:14:&amp;lt;h3&amp;gt; --&gt;&lt;h3 id="toc7"&gt;&lt;a name="Intervals--7/31 octave"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:14 --&gt;7/31 octave&lt;/h3&gt;
A 'subminor 3rd'.&lt;br /&gt;
&lt;br /&gt;
&lt;!-- ws:start:WikiTextHeadingRule:16:&amp;lt;h3&amp;gt; --&gt;&lt;h3 id="toc8"&gt;&lt;a name="Intervals--8/31 octave"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:16 --&gt;8/31 octave&lt;/h3&gt;
A minor third, closer to the just 6:5 than 12-edo, but not really close enough.&lt;br /&gt;
&lt;br /&gt;
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A neutral 3rd, practically equivalent to 11:9.&lt;br /&gt;
&lt;br /&gt;
&lt;!-- ws:start:WikiTextHeadingRule:20:&amp;lt;h3&amp;gt; --&gt;&lt;h3 id="toc10"&gt;&lt;a name="Intervals--10/31 octave"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:20 --&gt;10/31 octave&lt;/h3&gt;
A near-just major 3rd. Has led to the characterization of 31-edo as &amp;quot;smooth&amp;quot;.&lt;br /&gt;
&lt;br /&gt;
&lt;!-- ws:start:WikiTextHeadingRule:22:&amp;lt;h3&amp;gt; --&gt;&lt;h3 id="toc11"&gt;&lt;a name="Intervals--11/31 octave"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:22 --&gt;11/31 octave&lt;/h3&gt;
A 'supermajor 3rd'.&lt;br /&gt;
&lt;br /&gt;
&lt;!-- ws:start:WikiTextHeadingRule:24:&amp;lt;h3&amp;gt; --&gt;&lt;h3 id="toc12"&gt;&lt;a name="Intervals--12/31 octave"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:24 --&gt;12/31 octave&lt;/h3&gt;
A narrow fourth.&lt;br /&gt;
&lt;br /&gt;
&lt;!-- ws:start:WikiTextHeadingRule:26:&amp;lt;h3&amp;gt; --&gt;&lt;h3 id="toc13"&gt;&lt;a name="Intervals--13/31 octave"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:26 --&gt;13/31 octave&lt;/h3&gt;
Not very satisfying.&lt;br /&gt;
&lt;br /&gt;
&lt;!-- ws:start:WikiTextHeadingRule:28:&amp;lt;h3&amp;gt; --&gt;&lt;h3 id="toc14"&gt;&lt;a name="Intervals--14/31 octave"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:28 --&gt;14/31 octave&lt;/h3&gt;
10¢ off from a just 11:8; barely functional as such.&lt;br /&gt;
&lt;br /&gt;
&lt;!-- ws:start:WikiTextHeadingRule:30:&amp;lt;h3&amp;gt; --&gt;&lt;h3 id="toc15"&gt;&lt;a name="Intervals--15/31 octave"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:30 --&gt;15/31 octave&lt;/h3&gt;
The small tritone.&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
Nicola Vicentino had very nearly produced 31-equal temperament on his extended keyboard instrument, the Archicembalo, in 1555, but it was not until 1666 that Lemme Rossi first proposed it theoretically. Shortly thereafter, having discovered it independently, famed scientist Christiaan Huygens wrote about it also. Since the standard system of tuning at that time was quarter-comma meantone, in which the fifth is tuned to the fourth root of 5, the appeal of this method is immediate, as the fifth of 31-et, at 696.77 cents, is only a fifth of a cent sharper than the fifth of quarter-comma meantone. Huygens not only realized that, he went farther and noted that 31-et provides an excellent approximation of septimal, or 7-limit harmony, which was a very advanced insight for the time. In the twentieth century, physicist, music theorist and composer Adriaan Fokker, after reading Huygens's work, led a revival of interest in this system of tuning which led to a number of compositions, particularly by Dutch composers.&lt;br /&gt;
&lt;!-- ws:start:WikiTextHeadingRule:32:&amp;lt;h3&amp;gt; --&gt;&lt;h3 id="toc16"&gt;&lt;a name="Intervals--16/31 octave"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:32 --&gt;16/31 octave&lt;/h3&gt;
The large tritone.&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
&lt;!-- ws:start:WikiTextHeadingRule:0:&amp;lt;h1&amp;gt; --&gt;&lt;h1 id="toc0"&gt;&lt;a name="Theoretical properties"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:0 --&gt;Theoretical properties&lt;/h1&gt;
&lt;!-- ws:start:WikiTextHeadingRule:34:&amp;lt;h3&amp;gt; --&gt;&lt;h3 id="toc17"&gt;&lt;a name="Intervals--17/31 octave"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:34 --&gt;17/31 octave&lt;/h3&gt;
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&lt;!-- ws:start:WikiTextHeadingRule:62:&amp;lt;h3&amp;gt; --&gt;&lt;h3 id="toc31"&gt;&lt;a name="Intervals--perfect octave - 31/31 octave"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:62 --&gt;perfect octave - 31/31 octave&lt;/h3&gt;
  &lt;br /&gt;
  &lt;br /&gt;
The single most important fact about 31-et is that it equates to the unison, or ''tempers out'', the syntonic comma of 81/80. It is therefore a meantone temperament. It also tempers the 5-limit intervals 393216/390625, known as the Würschmidt comma after music theorist José Würschmidt, and 2109375/2097152, known as the semicomma.&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
More significantly, perhaps, it tempers out 126/125, the septimal semicomma, or starling comma. Because it tempers out both 81/80 and 126/125, it supports septimal meantone temperament. It also tempers out 1029/1024, the gamelan residue, and 1728/1715, the orwell comma. Consequently it supports a wide variety of &lt;a href="http://xenharmonic.wikispaces.com/Regular+Temperaments#lineartemperaments"&gt;linear temperaments&lt;/a&gt;.&lt;br /&gt;
&lt;!-- ws:start:WikiTextHeadingRule:64:&amp;lt;h1&amp;gt; --&gt;&lt;h1 id="toc32"&gt;&lt;a name="Modes"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:64 --&gt;Modes&lt;/h1&gt;
When 31 is too many alternatives to choose from.&lt;br /&gt;
&lt;br /&gt;
A large open list of modes (subsets) from 31-edo that people have named: &lt;a class="wiki_link" href="/31edo%20modes"&gt;31edo modes&lt;/a&gt;. Some of the popular ones:&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
&lt;!-- ws:start:WikiTextHeadingRule:2:&amp;lt;h2&amp;gt; --&gt;&lt;h2 id="toc1"&gt;&lt;a name="Theoretical properties-Chords of 31 equal temperament"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:2 --&gt;Chords of 31 equal temperament&lt;/h2&gt;
&lt;ul&gt;&lt;li&gt;31-tone major: 5 5 3 5 5 5 3&lt;/li&gt;&lt;li&gt;1/4-comma meantone (Eb-G#): 2 3 3 2 3 2 3 2 3 3 2 3&lt;/li&gt;&lt;li&gt;Harmonic scale 8: 5 5 4 4 4 4 3 3&lt;/li&gt;&lt;li&gt;the &lt;a class="wiki_link" href="/Euler-fokker%20genera"&gt;Euler-fokker genera&lt;/a&gt; (technically &lt;a class="wiki_link" href="/JI"&gt;JI&lt;/a&gt; but representable in 31)&lt;/li&gt;&lt;/ul&gt;&lt;br /&gt;
  &lt;br /&gt;
&lt;!-- ws:start:WikiTextHeadingRule:66:&amp;lt;h1&amp;gt; --&gt;&lt;h1 id="toc33"&gt;&lt;a name="Music in 31-edo"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:66 --&gt;Music in 31-edo&lt;/h1&gt;
Many of the most interesting chords of 31-et are those of septimal meantone temperament. Others are the neutral thirds triad, which might be written either C-Dx-G or C-Fbb-G, and the orwell tetrad, which is C-E-Fx-Bbb.&lt;br /&gt;
  &lt;a class="wiki_link" href="/31-edo%20compositions"&gt;An alphabetical list of Tricesimoprimal Compositions&lt;/a&gt;.&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
&lt;!-- ws:start:WikiTextHeadingRule:4:&amp;lt;h1&amp;gt; --&gt;&lt;h1 id="toc2"&gt;&lt;a name="Scales"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:4 --&gt;Scales&lt;/h1&gt;
&lt;!-- ws:start:WikiTextHeadingRule:68:&amp;lt;h2&amp;gt; --&gt;&lt;h2 id="toc34"&gt;&lt;a name="Music in 31-edo-Thirty-one tone pedagogy"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:68 --&gt;Thirty-one tone pedagogy&lt;/h2&gt;
  &lt;br /&gt;
  The &lt;a class="wiki_link" href="/MicroPedagogyCollective"&gt;MicroPedagogyCollective&lt;/a&gt; is currently at work producing demonstrative material which will encourage and enable more people to learn this system. There have been two &lt;a class="wiki_link" href="/ThirtyOneToneSinginCamp"&gt;ThirtyOneToneSinginCamp&lt;/a&gt;s as well.&lt;br /&gt;
&lt;a class="wiki_link" href="/shortspeak"&gt;31EDO interval naming scheme&lt;/a&gt;&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
&lt;!-- ws:start:WikiTextHeadingRule:6:&amp;lt;h2&amp;gt; --&gt;&lt;h2 id="toc3"&gt;&lt;a name="Scales-Septatonic tetrachordal scales"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:6 --&gt;Septatonic tetrachordal scales&lt;/h2&gt;
&lt;a class="wiki_link" href="/31edo%20Tetra%205-3-5"&gt;31edo Tetra 5-3-5&lt;/a&gt; &lt;a class="wiki_link" href="/31edo%20Tetra%205-4-4"&gt;31edo Tetra 5-4-4&lt;/a&gt; &lt;a class="wiki_link" href="/31edo%20Tetra%205-5-3"&gt;31edo Tetra 5-5-3&lt;/a&gt; &lt;a class="wiki_link" href="/31edo%20Tetra%205-6-2"&gt;31edo Tetra 5-6-2&lt;/a&gt; &lt;a class="wiki_link" href="/31edo%20Tetra%205-7-1"&gt;31edo Tetra 5-7-1&lt;/a&gt;&lt;br /&gt;
&lt;a class="wiki_link" href="/31edo%20Tetra%206-1-6"&gt;31edo Tetra 6-1-6&lt;/a&gt; &lt;a class="wiki_link" href="/31edo%20Tetra%206-2-5"&gt;31edo Tetra 6-2-5&lt;/a&gt; &lt;a class="wiki_link" href="/31edo%20Tetra%206-3-4"&gt;31edo Tetra 6-3-4&lt;/a&gt; &lt;a class="wiki_link" href="/31edo%20Tetra%206-4-3"&gt;31edo Tetra 6-4-3&lt;/a&gt; &lt;a class="wiki_link" href="/31edo%20Tetra%206-5-2"&gt;31edo Tetra 6-5-2&lt;/a&gt; &lt;a class="wiki_link" href="/31edo%20Tetra%206-6-1"&gt;31edo Tetra 6-6-1&lt;/a&gt;&lt;br /&gt;
&lt;a class="wiki_link" href="/31edo%20Tetra%207-1-5"&gt;31edo Tetra 7-1-5&lt;/a&gt; &lt;a class="wiki_link" href="/31edo%20Tetra%207-2-4"&gt;31edo Tetra 7-2-4&lt;/a&gt; &lt;a class="wiki_link" href="/31edo%20Tetra%207-3-3"&gt;31edo Tetra 7-3-3&lt;/a&gt; &lt;a class="wiki_link" href="/31edo%20Tetra%207-4-2"&gt;31edo Tetra 7-4-2&lt;/a&gt; &lt;a class="wiki_link" href="/31edo%20Tetra%207-5-1"&gt;31edo Tetra 7-5-1&lt;/a&gt;&lt;br /&gt;
&lt;a class="wiki_link" href="/31edo%20Tetra%208-1-4"&gt;31edo Tetra 8-1-4&lt;/a&gt; &lt;a class="wiki_link" href="/31edo%20Tetra%208-2-3"&gt;31edo Tetra 8-2-3&lt;/a&gt; &lt;a class="wiki_link" href="/31edo%20Tetra%208-4-1"&gt;31edo Tetra 8-4-1&lt;/a&gt;&lt;br /&gt;
&lt;a class="wiki_link" href="/31edo%20Tetra%209-1-3"&gt;31edo Tetra 9-1-3&lt;/a&gt; &lt;a class="wiki_link" href="/31edo%20Tetra%209-2-2"&gt;31edo Tetra 9-2-2&lt;/a&gt; &lt;a class="wiki_link" href="/31edo%20Tetra%209-3-1"&gt;31edo Tetra 9-3-1&lt;/a&gt;&lt;br /&gt;
&lt;a class="wiki_link" href="/31edo%20Tetra%2010-1-2"&gt;31edo Tetra 10-1-2&lt;/a&gt; &lt;a class="wiki_link" href="/31edo%20Tetra%2010-2-1"&gt;31edo Tetra 10-2-1&lt;/a&gt; &lt;a class="wiki_link" href="/31edo%20Tetra%2011-1-1"&gt;31edo Tetra 11-1-1&lt;/a&gt;&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
&lt;!-- ws:start:WikiTextHeadingRule:8:&amp;lt;h1&amp;gt; --&gt;&lt;h1 id="toc4"&gt;&lt;a name="External links"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:8 --&gt;External links&lt;/h1&gt;
&lt;!-- ws:start:WikiTextHeadingRule:70:&amp;lt;h1&amp;gt; --&gt;&lt;h1 id="toc35"&gt;&lt;a name="Other Articles"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:70 --&gt;Other Articles&lt;/h1&gt;
  &lt;ul&gt;&lt;li&gt;[&lt;a class="wiki_link_ext" href="http://www.xs4all.nl/%7Ehuygensf/english/index.html" rel="nofollow"&gt;http://www.xs4all.nl/~huygensf/english/index.html&lt;/a&gt; de Beer, Anton, ''The Development of 31-tone Music'']&lt;/li&gt;&lt;li&gt;[&lt;a class="wiki_link_ext" href="http://www.xs4all.nl/%7Ehuygensf/doc/fokkerorg.html" rel="nofollow"&gt;http://www.xs4all.nl/~huygensf/doc/fokkerorg.html&lt;/a&gt; Fokker, Adriaan Daniël, ''Equal Temperament and the Thirty-one-keyed organ'']&lt;/li&gt;&lt;li&gt;[&lt;a class="wiki_link_ext" href="http://www.xs4all.nl/%7Ehuygensf/doc/rap31.html" rel="nofollow"&gt;http://www.xs4all.nl/~huygensf/doc/rap31.html&lt;/a&gt; Rapoport, Paul, ''About 31-tone Equal Temperament'']&lt;/li&gt;&lt;li&gt;[&lt;a class="wiki_link_ext" href="http://www.xs4all.nl/%7Ehuygensf/doc/terp31.html" rel="nofollow"&gt;http://www.xs4all.nl/~huygensf/doc/terp31.html&lt;/a&gt; Terpstra, Siemen, ''Toward a Theory of Meantone (and 31-et) Harmony'']&lt;/li&gt;&lt;li&gt;[&lt;!-- ws:start:WikiTextUrlRule:85:http://tonalsoft.com/enc/number/31edo.aspx --&gt;&lt;a class="wiki_link_ext" href="http://tonalsoft.com/enc/number/31edo.aspx" rel="nofollow"&gt;http://tonalsoft.com/enc/number/31edo.aspx&lt;/a&gt;&lt;!-- ws:end:WikiTextUrlRule:85 --&gt; Tonalsoft Encyclopedia of Microtonal Music-theory]&lt;/li&gt;&lt;/ul&gt;&lt;/body&gt;&lt;/html&gt;</pre></div>
  &lt;ul&gt;&lt;li&gt;[&lt;span class="wiki_link_ext"&gt;[&lt;!-- ws:start:WikiTextUrlRule:203:http://www.xs4all.nl/~huygensf/english/index.html --&gt;&lt;a class="wiki_link_ext" href="http://www.xs4all.nl/~huygensf/english/index.html" rel="nofollow"&gt;http://www.xs4all.nl/~huygensf/english/index.html&lt;/a&gt;&lt;!-- ws:end:WikiTextUrlRule:203 --&gt;&lt;/span&gt;|de Beer, Anton, ''The Development of 31-tone Music'']]&lt;/li&gt;&lt;li&gt;[[&lt;span class="wiki_link_ext"&gt;&lt;!-- ws:start:WikiTextUrlRule:204:http://www.xs4all.nl/~huygensf/doc/fokkerorg.html --&gt;&lt;a class="wiki_link_ext" href="http://www.xs4all.nl/~huygensf/doc/fokkerorg.html" rel="nofollow"&gt;http://www.xs4all.nl/~huygensf/doc/fokkerorg.html&lt;/a&gt;&lt;!-- ws:end:WikiTextUrlRule:204 --&gt;&lt;/span&gt;|Fokker, Adriaan Daniël, ''Equal Temperament and the Thirty-one-keyed organ'']]&lt;/li&gt;&lt;li&gt;Fokker, A.D., &amp;quot;New Music with 31 Notes&amp;quot; translated by Leigh Gerdine&lt;/li&gt;&lt;li&gt;[[&lt;span class="wiki_link_ext"&gt;&lt;!-- ws:start:WikiTextUrlRule:205:http://www.xs4all.nl/~huygensf/doc/rap31.html --&gt;&lt;a class="wiki_link_ext" href="http://www.xs4all.nl/~huygensf/doc/rap31.html" rel="nofollow"&gt;http://www.xs4all.nl/~huygensf/doc/rap31.html&lt;/a&gt;&lt;!-- ws:end:WikiTextUrlRule:205 --&gt;&lt;/span&gt;|Rapoport, Paul, ''About 31-tone Equal Temperament'']* [[&lt;span class="wiki_link_ext"&gt;&lt;!-- ws:start:WikiTextUrlRule:206:http://www.xs4all.nl/~huygensf/doc/terp31.html --&gt;&lt;a class="wiki_link_ext" href="http://www.xs4all.nl/~huygensf/doc/terp31.html" rel="nofollow"&gt;http://www.xs4all.nl/~huygensf/doc/terp31.html&lt;/a&gt;&lt;!-- ws:end:WikiTextUrlRule:206 --&gt;&lt;/span&gt;|Terpstra, Siemen, ''Toward a Theory of Meantone (and 31-et) Harmony'']]&lt;/li&gt;&lt;li&gt;[[&lt;span class="wiki_link_ext"&gt;&lt;!-- ws:start:WikiTextUrlRule:207:http://tonalsoft.com/enc/number/31edo.aspx --&gt;&lt;a class="wiki_link_ext" href="http://tonalsoft.com/enc/number/31edo.aspx" rel="nofollow"&gt;http://tonalsoft.com/enc/number/31edo.aspx&lt;/a&gt;&lt;!-- ws:end:WikiTextUrlRule:207 --&gt;&lt;/span&gt;|Tonalsoft Encyclopedia article]&lt;/li&gt;&lt;/ul&gt;&lt;/body&gt;&lt;/html&gt;</pre></div>

Revision as of 15:10, 12 September 2008

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Original Wikitext content:

[[toc|flat]]

----
//Thirty-one tone equal temperament//, also called //31-tET//, //31-EDO//, //31-et//, or //tricesimoprimal temperament//, is the scale derived by dividing the octave into 31 [[equal|equally]] large steps. Each step is equivalent to a frequency ratio of the 31st root of 2, or 38.71 [[cents]].

For more encyclopedic info, see [[http://en.wikipedia.org/wiki/31_equal_temperament|Wikipedia's article]].

=Intervals= 
===Diesis - 1/31 octave=== 
A single step of 31-edo is about 38.7¢. Intervals around this size are called [[diesis|dieses]] (singular 'diesis'). In 31 it is equivalent to the difference between one octave and three stacked major thirds (C to E, to G#, to B#, but B# ≠ C), or four minor thirds (C to Eb to Gb to Bbb to Dbb ≠ C). Demonstrated in [[SpiralProgressions]].

===2/31 octave=== 
The difference between a major and minor third. The more 'expressive' of the 'half steps'.

===3/31 octave=== 
The difference between a perfect fourth and a major third. The larger and clunkier of the 'half steps'.

===Neutral second - 4/31 octave=== 
Exactly one half of the minor third.

===5/31 octave=== 
A rather smallish whole tone. Often called melodically dull.

===6/31 octave=== 
A 'supermajor 2nd'.

===7/31 octave=== 
A 'subminor 3rd'.

===8/31 octave=== 
A minor third, closer to the just 6:5 than 12-edo, but not really close enough.

===9/31 octave=== 
A neutral 3rd, practically equivalent to 11:9.

===10/31 octave=== 
A near-just major 3rd. Has led to the characterization of 31-edo as "smooth".

===11/31 octave=== 
A 'supermajor 3rd'.

===12/31 octave=== 
A narrow fourth.

===13/31 octave=== 
Not very satisfying.

===14/31 octave=== 
10¢ off from a just 11:8; barely functional as such.

===15/31 octave=== 
The small tritone.

===16/31 octave=== 
The large tritone.

===17/31 octave=== 
===18/31 octave=== 
===19/31 octave=== 
===20/31 octave=== 
===21/31 octave=== 
===22/31 octave=== 
===23/31 octave=== 
===24/31 octave=== 
===25/31 octave=== 
===26/31 octave=== 
===27/31 octave=== 
===28/31 octave=== 
===29/31 octave=== 
===30/31 octave=== 
===perfect octave - 31/31 octave=== 


=Modes= 
When 31 is too many alternatives to choose from.

A large open list of modes (subsets) from 31-edo that people have named: [[31edo modes]]. Some of the popular ones:

* 31-tone major: 5 5 3 5 5 5 3
* 1/4-comma meantone (Eb-G#): 2 3 3 2 3 2 3 2 3 3 2 3
* Harmonic scale 8: 5 5 4 4 4 4 3 3
* the [[Euler-fokker genera]] (technically [[JI]] but representable in 31) 

=Music in 31-edo= 
[[31-edo compositions|An alphabetical list of Tricesimoprimal Compositions]].

==Thirty-one tone pedagogy== 
The [[MicroPedagogyCollective]] is currently at work producing demonstrative material which will encourage and enable more people to learn this system. There have been two [[ThirtyOneToneSinginCamp]]s as well.


=Other Articles= 
* [<span class="wiki_link_ext">[http://www.xs4all.nl/~huygensf/english/index.html</span>|de Beer, Anton, ''The Development of 31-tone Music'']]
* [[<span class="wiki_link_ext">http://www.xs4all.nl/~huygensf/doc/fokkerorg.html</span>|Fokker, Adriaan Daniël, ''Equal Temperament and the Thirty-one-keyed organ'']]
* Fokker, A.D., "New Music with 31 Notes" translated by Leigh Gerdine
* [[<span class="wiki_link_ext">http://www.xs4all.nl/~huygensf/doc/rap31.html</span>|Rapoport, Paul, ''About 31-tone Equal Temperament'']
* [[<span class="wiki_link_ext">http://www.xs4all.nl/~huygensf/doc/terp31.html</span>|Terpstra, Siemen, ''Toward a Theory of Meantone (and 31-et) Harmony'']]
* [[<span class="wiki_link_ext">http://tonalsoft.com/enc/number/31edo.aspx</span>|Tonalsoft Encyclopedia article]

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<html><head><title>31edo</title></head><body><!-- ws:start:WikiTextTocRule:72:&lt;img id=&quot;wikitext@@toc@@flat&quot; class=&quot;WikiMedia WikiMediaTocFlat&quot; title=&quot;Table of Contents&quot; src=&quot;/site/embedthumbnail/toc/flat?w=100&amp;h=16&quot;/&gt; --><!-- ws:end:WikiTextTocRule:72 --><!-- ws:start:WikiTextTocRule:73: --><a href="#Intervals">Intervals</a><!-- ws:end:WikiTextTocRule:73 --><!-- ws:start:WikiTextTocRule:74: --><!-- ws:end:WikiTextTocRule:74 --><!-- ws:start:WikiTextTocRule:75: --><!-- ws:end:WikiTextTocRule:75 --><!-- ws:start:WikiTextTocRule:76: --><!-- ws:end:WikiTextTocRule:76 --><!-- ws:start:WikiTextTocRule:77: --><!-- ws:end:WikiTextTocRule:77 --><!-- ws:start:WikiTextTocRule:78: --><!-- ws:end:WikiTextTocRule:78 --><!-- ws:start:WikiTextTocRule:79: --><!-- ws:end:WikiTextTocRule:79 --><!-- ws:start:WikiTextTocRule:80: --><!-- ws:end:WikiTextTocRule:80 --><!-- ws:start:WikiTextTocRule:81: --><!-- ws:end:WikiTextTocRule:81 --><!-- ws:start:WikiTextTocRule:82: --><!-- ws:end:WikiTextTocRule:82 --><!-- ws:start:WikiTextTocRule:83: --><!-- ws:end:WikiTextTocRule:83 --><!-- ws:start:WikiTextTocRule:84: --><!-- ws:end:WikiTextTocRule:84 --><!-- ws:start:WikiTextTocRule:85: --><!-- ws:end:WikiTextTocRule:85 --><!-- ws:start:WikiTextTocRule:86: --><!-- ws:end:WikiTextTocRule:86 --><!-- ws:start:WikiTextTocRule:87: --><!-- ws:end:WikiTextTocRule:87 --><!-- ws:start:WikiTextTocRule:88: --><!-- ws:end:WikiTextTocRule:88 --><!-- ws:start:WikiTextTocRule:89: --><!-- ws:end:WikiTextTocRule:89 --><!-- ws:start:WikiTextTocRule:90: --><!-- ws:end:WikiTextTocRule:90 --><!-- ws:start:WikiTextTocRule:91: --><!-- ws:end:WikiTextTocRule:91 --><!-- ws:start:WikiTextTocRule:92: --><!-- ws:end:WikiTextTocRule:92 --><!-- ws:start:WikiTextTocRule:93: --><!-- ws:end:WikiTextTocRule:93 --><!-- ws:start:WikiTextTocRule:94: --><!-- ws:end:WikiTextTocRule:94 --><!-- ws:start:WikiTextTocRule:95: --><!-- ws:end:WikiTextTocRule:95 --><!-- ws:start:WikiTextTocRule:96: --><!-- ws:end:WikiTextTocRule:96 --><!-- ws:start:WikiTextTocRule:97: --><!-- ws:end:WikiTextTocRule:97 --><!-- ws:start:WikiTextTocRule:98: --><!-- ws:end:WikiTextTocRule:98 --><!-- ws:start:WikiTextTocRule:99: --><!-- ws:end:WikiTextTocRule:99 --><!-- ws:start:WikiTextTocRule:100: --><!-- ws:end:WikiTextTocRule:100 --><!-- ws:start:WikiTextTocRule:101: --><!-- ws:end:WikiTextTocRule:101 --><!-- ws:start:WikiTextTocRule:102: --><!-- ws:end:WikiTextTocRule:102 --><!-- ws:start:WikiTextTocRule:103: --><!-- ws:end:WikiTextTocRule:103 --><!-- ws:start:WikiTextTocRule:104: --><!-- ws:end:WikiTextTocRule:104 --><!-- ws:start:WikiTextTocRule:105: --> | <a href="#Modes">Modes</a><!-- ws:end:WikiTextTocRule:105 --><!-- ws:start:WikiTextTocRule:106: --> | <a href="#Music in 31-edo">Music in 31-edo</a><!-- ws:end:WikiTextTocRule:106 --><!-- ws:start:WikiTextTocRule:107: --><!-- ws:end:WikiTextTocRule:107 --><!-- ws:start:WikiTextTocRule:108: --> | <a href="#Other Articles">Other Articles</a><!-- ws:end:WikiTextTocRule:108 --><!-- ws:start:WikiTextTocRule:109: -->
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<em>Thirty-one tone equal temperament</em>, also called <em>31-tET</em>, <em>31-EDO</em>, <em>31-et</em>, or <em>tricesimoprimal temperament</em>, is the scale derived by dividing the octave into 31 <a class="wiki_link" href="/equal">equally</a> large steps. Each step is equivalent to a frequency ratio of the 31st root of 2, or 38.71 <a class="wiki_link" href="/cents">cents</a>.<br />
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For more encyclopedic info, see <a class="wiki_link_ext" href="http://en.wikipedia.org/wiki/31_equal_temperament" rel="nofollow">Wikipedia's article</a>.<br />
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<!-- ws:start:WikiTextHeadingRule:0:&lt;h1&gt; --><h1 id="toc0"><a name="Intervals"></a><!-- ws:end:WikiTextHeadingRule:0 -->Intervals</h1>
 <!-- ws:start:WikiTextHeadingRule:2:&lt;h3&gt; --><h3 id="toc1"><a name="Intervals--Diesis - 1/31 octave"></a><!-- ws:end:WikiTextHeadingRule:2 -->Diesis - 1/31 octave</h3>
 A single step of 31-edo is about 38.7¢. Intervals around this size are called <a class="wiki_link" href="/diesis">dieses</a> (singular 'diesis'). In 31 it is equivalent to the difference between one octave and three stacked major thirds (C to E, to G#, to B#, but B# ≠ C), or four minor thirds (C to Eb to Gb to Bbb to Dbb ≠ C). Demonstrated in <a class="wiki_link" href="/SpiralProgressions">SpiralProgressions</a>.<br />
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<!-- ws:start:WikiTextHeadingRule:4:&lt;h3&gt; --><h3 id="toc2"><a name="Intervals--2/31 octave"></a><!-- ws:end:WikiTextHeadingRule:4 -->2/31 octave</h3>
 The difference between a major and minor third. The more 'expressive' of the 'half steps'.<br />
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<!-- ws:start:WikiTextHeadingRule:6:&lt;h3&gt; --><h3 id="toc3"><a name="Intervals--3/31 octave"></a><!-- ws:end:WikiTextHeadingRule:6 -->3/31 octave</h3>
 The difference between a perfect fourth and a major third. The larger and clunkier of the 'half steps'.<br />
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<!-- ws:start:WikiTextHeadingRule:8:&lt;h3&gt; --><h3 id="toc4"><a name="Intervals--Neutral second - 4/31 octave"></a><!-- ws:end:WikiTextHeadingRule:8 -->Neutral second - 4/31 octave</h3>
 Exactly one half of the minor third.<br />
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<!-- ws:start:WikiTextHeadingRule:10:&lt;h3&gt; --><h3 id="toc5"><a name="Intervals--5/31 octave"></a><!-- ws:end:WikiTextHeadingRule:10 -->5/31 octave</h3>
 A rather smallish whole tone. Often called melodically dull.<br />
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<!-- ws:start:WikiTextHeadingRule:12:&lt;h3&gt; --><h3 id="toc6"><a name="Intervals--6/31 octave"></a><!-- ws:end:WikiTextHeadingRule:12 -->6/31 octave</h3>
 A 'supermajor 2nd'.<br />
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<!-- ws:start:WikiTextHeadingRule:14:&lt;h3&gt; --><h3 id="toc7"><a name="Intervals--7/31 octave"></a><!-- ws:end:WikiTextHeadingRule:14 -->7/31 octave</h3>
 A 'subminor 3rd'.<br />
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<!-- ws:start:WikiTextHeadingRule:16:&lt;h3&gt; --><h3 id="toc8"><a name="Intervals--8/31 octave"></a><!-- ws:end:WikiTextHeadingRule:16 -->8/31 octave</h3>
 A minor third, closer to the just 6:5 than 12-edo, but not really close enough.<br />
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<!-- ws:start:WikiTextHeadingRule:18:&lt;h3&gt; --><h3 id="toc9"><a name="Intervals--9/31 octave"></a><!-- ws:end:WikiTextHeadingRule:18 -->9/31 octave</h3>
 A neutral 3rd, practically equivalent to 11:9.<br />
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<!-- ws:start:WikiTextHeadingRule:20:&lt;h3&gt; --><h3 id="toc10"><a name="Intervals--10/31 octave"></a><!-- ws:end:WikiTextHeadingRule:20 -->10/31 octave</h3>
 A near-just major 3rd. Has led to the characterization of 31-edo as &quot;smooth&quot;.<br />
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<!-- ws:start:WikiTextHeadingRule:22:&lt;h3&gt; --><h3 id="toc11"><a name="Intervals--11/31 octave"></a><!-- ws:end:WikiTextHeadingRule:22 -->11/31 octave</h3>
 A 'supermajor 3rd'.<br />
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<!-- ws:start:WikiTextHeadingRule:24:&lt;h3&gt; --><h3 id="toc12"><a name="Intervals--12/31 octave"></a><!-- ws:end:WikiTextHeadingRule:24 -->12/31 octave</h3>
 A narrow fourth.<br />
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<!-- ws:start:WikiTextHeadingRule:26:&lt;h3&gt; --><h3 id="toc13"><a name="Intervals--13/31 octave"></a><!-- ws:end:WikiTextHeadingRule:26 -->13/31 octave</h3>
 Not very satisfying.<br />
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<!-- ws:start:WikiTextHeadingRule:28:&lt;h3&gt; --><h3 id="toc14"><a name="Intervals--14/31 octave"></a><!-- ws:end:WikiTextHeadingRule:28 -->14/31 octave</h3>
 10¢ off from a just 11:8; barely functional as such.<br />
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<!-- ws:start:WikiTextHeadingRule:30:&lt;h3&gt; --><h3 id="toc15"><a name="Intervals--15/31 octave"></a><!-- ws:end:WikiTextHeadingRule:30 -->15/31 octave</h3>
 The small tritone.<br />
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<!-- ws:start:WikiTextHeadingRule:32:&lt;h3&gt; --><h3 id="toc16"><a name="Intervals--16/31 octave"></a><!-- ws:end:WikiTextHeadingRule:32 -->16/31 octave</h3>
 The large tritone.<br />
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<!-- ws:start:WikiTextHeadingRule:34:&lt;h3&gt; --><h3 id="toc17"><a name="Intervals--17/31 octave"></a><!-- ws:end:WikiTextHeadingRule:34 -->17/31 octave</h3>
 <!-- ws:start:WikiTextHeadingRule:36:&lt;h3&gt; --><h3 id="toc18"><a name="Intervals--18/31 octave"></a><!-- ws:end:WikiTextHeadingRule:36 -->18/31 octave</h3>
 <!-- ws:start:WikiTextHeadingRule:38:&lt;h3&gt; --><h3 id="toc19"><a name="Intervals--19/31 octave"></a><!-- ws:end:WikiTextHeadingRule:38 -->19/31 octave</h3>
 <!-- ws:start:WikiTextHeadingRule:40:&lt;h3&gt; --><h3 id="toc20"><a name="Intervals--20/31 octave"></a><!-- ws:end:WikiTextHeadingRule:40 -->20/31 octave</h3>
 <!-- ws:start:WikiTextHeadingRule:42:&lt;h3&gt; --><h3 id="toc21"><a name="Intervals--21/31 octave"></a><!-- ws:end:WikiTextHeadingRule:42 -->21/31 octave</h3>
 <!-- ws:start:WikiTextHeadingRule:44:&lt;h3&gt; --><h3 id="toc22"><a name="Intervals--22/31 octave"></a><!-- ws:end:WikiTextHeadingRule:44 -->22/31 octave</h3>
 <!-- ws:start:WikiTextHeadingRule:46:&lt;h3&gt; --><h3 id="toc23"><a name="Intervals--23/31 octave"></a><!-- ws:end:WikiTextHeadingRule:46 -->23/31 octave</h3>
 <!-- ws:start:WikiTextHeadingRule:48:&lt;h3&gt; --><h3 id="toc24"><a name="Intervals--24/31 octave"></a><!-- ws:end:WikiTextHeadingRule:48 -->24/31 octave</h3>
 <!-- ws:start:WikiTextHeadingRule:50:&lt;h3&gt; --><h3 id="toc25"><a name="Intervals--25/31 octave"></a><!-- ws:end:WikiTextHeadingRule:50 -->25/31 octave</h3>
 <!-- ws:start:WikiTextHeadingRule:52:&lt;h3&gt; --><h3 id="toc26"><a name="Intervals--26/31 octave"></a><!-- ws:end:WikiTextHeadingRule:52 -->26/31 octave</h3>
 <!-- ws:start:WikiTextHeadingRule:54:&lt;h3&gt; --><h3 id="toc27"><a name="Intervals--27/31 octave"></a><!-- ws:end:WikiTextHeadingRule:54 -->27/31 octave</h3>
 <!-- ws:start:WikiTextHeadingRule:56:&lt;h3&gt; --><h3 id="toc28"><a name="Intervals--28/31 octave"></a><!-- ws:end:WikiTextHeadingRule:56 -->28/31 octave</h3>
 <!-- ws:start:WikiTextHeadingRule:58:&lt;h3&gt; --><h3 id="toc29"><a name="Intervals--29/31 octave"></a><!-- ws:end:WikiTextHeadingRule:58 -->29/31 octave</h3>
 <!-- ws:start:WikiTextHeadingRule:60:&lt;h3&gt; --><h3 id="toc30"><a name="Intervals--30/31 octave"></a><!-- ws:end:WikiTextHeadingRule:60 -->30/31 octave</h3>
 <!-- ws:start:WikiTextHeadingRule:62:&lt;h3&gt; --><h3 id="toc31"><a name="Intervals--perfect octave - 31/31 octave"></a><!-- ws:end:WikiTextHeadingRule:62 -->perfect octave - 31/31 octave</h3>
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<!-- ws:start:WikiTextHeadingRule:64:&lt;h1&gt; --><h1 id="toc32"><a name="Modes"></a><!-- ws:end:WikiTextHeadingRule:64 -->Modes</h1>
 When 31 is too many alternatives to choose from.<br />
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A large open list of modes (subsets) from 31-edo that people have named: <a class="wiki_link" href="/31edo%20modes">31edo modes</a>. Some of the popular ones:<br />
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<ul><li>31-tone major: 5 5 3 5 5 5 3</li><li>1/4-comma meantone (Eb-G#): 2 3 3 2 3 2 3 2 3 3 2 3</li><li>Harmonic scale 8: 5 5 4 4 4 4 3 3</li><li>the <a class="wiki_link" href="/Euler-fokker%20genera">Euler-fokker genera</a> (technically <a class="wiki_link" href="/JI">JI</a> but representable in 31)</li></ul><br />
<!-- ws:start:WikiTextHeadingRule:66:&lt;h1&gt; --><h1 id="toc33"><a name="Music in 31-edo"></a><!-- ws:end:WikiTextHeadingRule:66 -->Music in 31-edo</h1>
 <a class="wiki_link" href="/31-edo%20compositions">An alphabetical list of Tricesimoprimal Compositions</a>.<br />
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<!-- ws:start:WikiTextHeadingRule:68:&lt;h2&gt; --><h2 id="toc34"><a name="Music in 31-edo-Thirty-one tone pedagogy"></a><!-- ws:end:WikiTextHeadingRule:68 -->Thirty-one tone pedagogy</h2>
 The <a class="wiki_link" href="/MicroPedagogyCollective">MicroPedagogyCollective</a> is currently at work producing demonstrative material which will encourage and enable more people to learn this system. There have been two <a class="wiki_link" href="/ThirtyOneToneSinginCamp">ThirtyOneToneSinginCamp</a>s as well.<br />
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<!-- ws:start:WikiTextHeadingRule:70:&lt;h1&gt; --><h1 id="toc35"><a name="Other Articles"></a><!-- ws:end:WikiTextHeadingRule:70 -->Other Articles</h1>
 <ul><li>[<span class="wiki_link_ext">[<!-- ws:start:WikiTextUrlRule:203:http://www.xs4all.nl/~huygensf/english/index.html --><a class="wiki_link_ext" href="http://www.xs4all.nl/~huygensf/english/index.html" rel="nofollow">http://www.xs4all.nl/~huygensf/english/index.html</a><!-- ws:end:WikiTextUrlRule:203 --></span>|de Beer, Anton, ''The Development of 31-tone Music'']]</li><li>[[<span class="wiki_link_ext"><!-- ws:start:WikiTextUrlRule:204:http://www.xs4all.nl/~huygensf/doc/fokkerorg.html --><a class="wiki_link_ext" href="http://www.xs4all.nl/~huygensf/doc/fokkerorg.html" rel="nofollow">http://www.xs4all.nl/~huygensf/doc/fokkerorg.html</a><!-- ws:end:WikiTextUrlRule:204 --></span>|Fokker, Adriaan Daniël, ''Equal Temperament and the Thirty-one-keyed organ'']]</li><li>Fokker, A.D., &quot;New Music with 31 Notes&quot; translated by Leigh Gerdine</li><li>[[<span class="wiki_link_ext"><!-- ws:start:WikiTextUrlRule:205:http://www.xs4all.nl/~huygensf/doc/rap31.html --><a class="wiki_link_ext" href="http://www.xs4all.nl/~huygensf/doc/rap31.html" rel="nofollow">http://www.xs4all.nl/~huygensf/doc/rap31.html</a><!-- ws:end:WikiTextUrlRule:205 --></span>|Rapoport, Paul, ''About 31-tone Equal Temperament'']* [[<span class="wiki_link_ext"><!-- ws:start:WikiTextUrlRule:206:http://www.xs4all.nl/~huygensf/doc/terp31.html --><a class="wiki_link_ext" href="http://www.xs4all.nl/~huygensf/doc/terp31.html" rel="nofollow">http://www.xs4all.nl/~huygensf/doc/terp31.html</a><!-- ws:end:WikiTextUrlRule:206 --></span>|Terpstra, Siemen, ''Toward a Theory of Meantone (and 31-et) Harmony'']]</li><li>[[<span class="wiki_link_ext"><!-- ws:start:WikiTextUrlRule:207:http://tonalsoft.com/enc/number/31edo.aspx --><a class="wiki_link_ext" href="http://tonalsoft.com/enc/number/31edo.aspx" rel="nofollow">http://tonalsoft.com/enc/number/31edo.aspx</a><!-- ws:end:WikiTextUrlRule:207 --></span>|Tonalsoft Encyclopedia article]</li></ul></body></html>