18edo: Difference between revisions

Wikispaces>xenwolf
**Imported revision 139248063 - Original comment: **
Wikispaces>xenwolf
**Imported revision 139248817 - Original comment: simplified structure :-) Are there any good examples for listening?**
Line 1: Line 1:
<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:xenwolf|xenwolf]] and made on <tt>2010-05-04 03:23:54 UTC</tt>.<br>
: This revision was by author [[User:xenwolf|xenwolf]] and made on <tt>2010-05-04 03:31:43 UTC</tt>.<br>
: The original revision id was <tt>139248063</tt>.<br>
: The original revision id was <tt>139248817</tt>.<br>
: The revision comment was: <tt></tt><br>
: The revision comment was: <tt>simplified structure :-) Are there any good examples for listening?</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>
<h4>Original Wikitext content:</h4>
<h4>Original Wikitext content:</h4>
<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">=18 Equal Divisions of the Octave=  
<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">=18 Equal Divisions of the Octave=  
AKA The Third-Tone System
AKA The Third-Tone System
== ==  
==Basic Properties==  
==**Basic Properties**==
=== Representations of Just Intervals ===
&lt;span style="font-size: 14px; line-height: 21px;"&gt;**Representations of Just Intervals**&lt;/span&gt;
|| Degree || Cents || Nearest Ratio || Error (cents) ||
|| Degree || Cents || Nearest Ratio || Error (cents) ||
|| 0 || 0 || 1/1 || 0 ||
|| 0 || 0 || 1/1 || 0 ||
Line 33: Line 32:
18-EDO does not approximate the 3rd Harmonic at all, unless a &gt;30¢-error is considered acceptable. This makes it unsuitable for rendering common-practice music. However, it does offer excellent approximations of 27/25, 9/8, 7/6, 17/14, 21/16, and 15/11 (and their respective reciprocal intervals), so it is still capable of playing consonant music; however, in order to access these consonances, one must take a considerably "non-common-practice" approach.
18-EDO does not approximate the 3rd Harmonic at all, unless a &gt;30¢-error is considered acceptable. This makes it unsuitable for rendering common-practice music. However, it does offer excellent approximations of 27/25, 9/8, 7/6, 17/14, 21/16, and 15/11 (and their respective reciprocal intervals), so it is still capable of playing consonant music; however, in order to access these consonances, one must take a considerably "non-common-practice" approach.


&lt;span style="font-size: 14px; line-height: 21px;"&gt;**Relationship to Other EDOs** &lt;/span&gt;
=== Relationship to Other EDOs ===
18-EDO, aka the "third-tone" system, is related to [[12edo|12-tET]] by the whole-tone scale (which is [[6edo|6-EDO]]), since 18=6*3 and 12=6*2; hence a 12-tET "whole tone" is divided into 3 equal parts in 18-EDO. Since 18=9*2, 18-EDO contains two sets of [[9edo|9-EDO]], offset from each other by a third-tone. 18-EDO is related to [[13edo|13-EDO]], [[21edo|21-EDO]], [[23edo|23-EDO]], and [[28edo|28-EDO]] in that all are [[Father Temperament|"Father" temperaments]] (they temper out 16/15--the difference between a major third and perfect fourth). It is related to [[11edo|11-EDO]], [[15edo|15-EDO]], [[25edo|25-EDO]], and [[19edo|29-EDO]] in that they are all [[Amity Temperament|"Amity" temperaments]] ("Amity" is derived from the acronym of "Acute Minor Thirds", meaning a minor third sharper than 6/5 but still flatter than a neutral third).
18-EDO, aka the "third-tone" system, is related to [[12edo|12-tET]] by the whole-tone scale (which is [[6edo|6-EDO]]), since 18=6*3 and 12=6*2; hence a 12-tET "whole tone" is divided into 3 equal parts in 18-EDO. Since 18=9*2, 18-EDO contains two sets of [[9edo|9-EDO]], offset from each other by a third-tone. 18-EDO is related to [[13edo|13-EDO]], [[21edo|21-EDO]], [[23edo|23-EDO]], and [[28edo|28-EDO]] in that all are [[Father Temperament|"Father" temperaments]] (they temper out 16/15--the difference between a major third and perfect fourth). It is related to [[11edo|11-EDO]], [[15edo|15-EDO]], [[25edo|25-EDO]], and [[19edo|29-EDO]] in that they are all [[Amity Temperament|"Amity" temperaments]] ("Amity" is derived from the acronym of "Acute Minor Thirds", meaning a minor third sharper than 6/5 but still flatter than a neutral third).


Line 59: Line 58:
<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;18edo&lt;/title&gt;&lt;/head&gt;&lt;body&gt;&lt;!-- ws:start:WikiTextHeadingRule:0:&amp;lt;h1&amp;gt; --&gt;&lt;h1 id="toc0"&gt;&lt;a name="x18 Equal Divisions of the Octave"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:0 --&gt;18 Equal Divisions of the Octave&lt;/h1&gt;
<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;18edo&lt;/title&gt;&lt;/head&gt;&lt;body&gt;&lt;!-- ws:start:WikiTextHeadingRule:0:&amp;lt;h1&amp;gt; --&gt;&lt;h1 id="toc0"&gt;&lt;a name="x18 Equal Divisions of the Octave"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:0 --&gt;18 Equal Divisions of the Octave&lt;/h1&gt;
  AKA The Third-Tone System&lt;br /&gt;
  AKA The Third-Tone System&lt;br /&gt;
&lt;!-- ws:start:WikiTextHeadingRule:2:&amp;lt;h2&amp;gt; --&gt;&lt;h2 id="toc1"&gt;&lt;!-- ws:end:WikiTextHeadingRule:2 --&gt; &lt;/h2&gt;
&lt;!-- ws:start:WikiTextHeadingRule:2:&amp;lt;h2&amp;gt; --&gt;&lt;h2 id="toc1"&gt;&lt;a name="x18 Equal Divisions of the Octave-Basic Properties"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:2 --&gt;Basic Properties&lt;/h2&gt;
  &lt;!-- ws:start:WikiTextHeadingRule:4:&amp;lt;h2&amp;gt; --&gt;&lt;h2 id="toc2"&gt;&lt;a name="x18 Equal Divisions of the Octave-Basic Properties"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:4 --&gt;&lt;strong&gt;Basic Properties&lt;/strong&gt;&lt;/h2&gt;
  &lt;!-- ws:start:WikiTextHeadingRule:4:&amp;lt;h3&amp;gt; --&gt;&lt;h3 id="toc2"&gt;&lt;a name="x18 Equal Divisions of the Octave-Basic Properties-Representations of Just Intervals"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:4 --&gt; Representations of Just Intervals &lt;/h3&gt;
&lt;span style="font-size: 14px; line-height: 21px;"&gt;&lt;strong&gt;Representations of Just Intervals&lt;/strong&gt;&lt;/span&gt;&lt;br /&gt;




Line 269: Line 267:
18-EDO does not approximate the 3rd Harmonic at all, unless a &amp;gt;30¢-error is considered acceptable. This makes it unsuitable for rendering common-practice music. However, it does offer excellent approximations of 27/25, 9/8, 7/6, 17/14, 21/16, and 15/11 (and their respective reciprocal intervals), so it is still capable of playing consonant music; however, in order to access these consonances, one must take a considerably &amp;quot;non-common-practice&amp;quot; approach.&lt;br /&gt;
18-EDO does not approximate the 3rd Harmonic at all, unless a &amp;gt;30¢-error is considered acceptable. This makes it unsuitable for rendering common-practice music. However, it does offer excellent approximations of 27/25, 9/8, 7/6, 17/14, 21/16, and 15/11 (and their respective reciprocal intervals), so it is still capable of playing consonant music; however, in order to access these consonances, one must take a considerably &amp;quot;non-common-practice&amp;quot; approach.&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
&lt;span style="font-size: 14px; line-height: 21px;"&gt;&lt;strong&gt;Relationship to Other EDOs&lt;/strong&gt; &lt;/span&gt;&lt;br /&gt;
&lt;!-- ws:start:WikiTextHeadingRule:6:&amp;lt;h3&amp;gt; --&gt;&lt;h3 id="toc3"&gt;&lt;a name="x18 Equal Divisions of the Octave-Basic Properties-Relationship to Other EDOs"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:6 --&gt; Relationship to Other EDOs &lt;/h3&gt;
18-EDO, aka the &amp;quot;third-tone&amp;quot; system, is related to &lt;a class="wiki_link" href="/12edo"&gt;12-tET&lt;/a&gt; by the whole-tone scale (which is &lt;a class="wiki_link" href="/6edo"&gt;6-EDO&lt;/a&gt;), since 18=6*3 and 12=6*2; hence a 12-tET &amp;quot;whole tone&amp;quot; is divided into 3 equal parts in 18-EDO. Since 18=9*2, 18-EDO contains two sets of &lt;a class="wiki_link" href="/9edo"&gt;9-EDO&lt;/a&gt;, offset from each other by a third-tone. 18-EDO is related to &lt;a class="wiki_link" href="/13edo"&gt;13-EDO&lt;/a&gt;, &lt;a class="wiki_link" href="/21edo"&gt;21-EDO&lt;/a&gt;, &lt;a class="wiki_link" href="/23edo"&gt;23-EDO&lt;/a&gt;, and &lt;a class="wiki_link" href="/28edo"&gt;28-EDO&lt;/a&gt; in that all are &lt;a class="wiki_link" href="/Father%20Temperament"&gt;&amp;quot;Father&amp;quot; temperaments&lt;/a&gt; (they temper out 16/15--the difference between a major third and perfect fourth). It is related to &lt;a class="wiki_link" href="/11edo"&gt;11-EDO&lt;/a&gt;, &lt;a class="wiki_link" href="/15edo"&gt;15-EDO&lt;/a&gt;, &lt;a class="wiki_link" href="/25edo"&gt;25-EDO&lt;/a&gt;, and &lt;a class="wiki_link" href="/19edo"&gt;29-EDO&lt;/a&gt; in that they are all &lt;a class="wiki_link" href="/Amity%20Temperament"&gt;&amp;quot;Amity&amp;quot; temperaments&lt;/a&gt; (&amp;quot;Amity&amp;quot; is derived from the acronym of &amp;quot;Acute Minor Thirds&amp;quot;, meaning a minor third sharper than 6/5 but still flatter than a neutral third).&lt;br /&gt;
18-EDO, aka the &amp;quot;third-tone&amp;quot; system, is related to &lt;a class="wiki_link" href="/12edo"&gt;12-tET&lt;/a&gt; by the whole-tone scale (which is &lt;a class="wiki_link" href="/6edo"&gt;6-EDO&lt;/a&gt;), since 18=6*3 and 12=6*2; hence a 12-tET &amp;quot;whole tone&amp;quot; is divided into 3 equal parts in 18-EDO. Since 18=9*2, 18-EDO contains two sets of &lt;a class="wiki_link" href="/9edo"&gt;9-EDO&lt;/a&gt;, offset from each other by a third-tone. 18-EDO is related to &lt;a class="wiki_link" href="/13edo"&gt;13-EDO&lt;/a&gt;, &lt;a class="wiki_link" href="/21edo"&gt;21-EDO&lt;/a&gt;, &lt;a class="wiki_link" href="/23edo"&gt;23-EDO&lt;/a&gt;, and &lt;a class="wiki_link" href="/28edo"&gt;28-EDO&lt;/a&gt; in that all are &lt;a class="wiki_link" href="/Father%20Temperament"&gt;&amp;quot;Father&amp;quot; temperaments&lt;/a&gt; (they temper out 16/15--the difference between a major third and perfect fourth). It is related to &lt;a class="wiki_link" href="/11edo"&gt;11-EDO&lt;/a&gt;, &lt;a class="wiki_link" href="/15edo"&gt;15-EDO&lt;/a&gt;, &lt;a class="wiki_link" href="/25edo"&gt;25-EDO&lt;/a&gt;, and &lt;a class="wiki_link" href="/19edo"&gt;29-EDO&lt;/a&gt; in that they are all &lt;a class="wiki_link" href="/Amity%20Temperament"&gt;&amp;quot;Amity&amp;quot; temperaments&lt;/a&gt; (&amp;quot;Amity&amp;quot; is derived from the acronym of &amp;quot;Acute Minor Thirds&amp;quot;, meaning a minor third sharper than 6/5 but still flatter than a neutral third).&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="x18 Equal Divisions of the Octave-Useful Moment-of-Symmetry Scales"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:6 --&gt;Useful Moment-of-Symmetry Scales&lt;/h2&gt;
&lt;!-- ws:start:WikiTextHeadingRule:8:&amp;lt;h2&amp;gt; --&gt;&lt;h2 id="toc4"&gt;&lt;a name="x18 Equal Divisions of the Octave-Useful Moment-of-Symmetry Scales"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:8 --&gt;Useful Moment-of-Symmetry Scales&lt;/h2&gt;
  Note: This list excludes scales found in 9-EDO.&lt;br /&gt;
  Note: This list excludes scales found in 9-EDO.&lt;br /&gt;
&lt;!-- ws:start:WikiTextHeadingRule:8:&amp;lt;h3&amp;gt; --&gt;&lt;h3 id="toc4"&gt;&lt;a name="x18 Equal Divisions of the Octave-Useful Moment-of-Symmetry Scales-Pentatonic:"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:8 --&gt;Pentatonic:&lt;/h3&gt;
&lt;!-- ws:start:WikiTextHeadingRule:10:&amp;lt;h3&amp;gt; --&gt;&lt;h3 id="toc5"&gt;&lt;a name="x18 Equal Divisions of the Octave-Useful Moment-of-Symmetry Scales-Pentatonic:"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:10 --&gt;Pentatonic:&lt;/h3&gt;
  Father Pentatonic: 4 4 3 4 3&lt;br /&gt;
  Father Pentatonic: 4 4 3 4 3&lt;br /&gt;
&lt;!-- ws:start:WikiTextHeadingRule:10:&amp;lt;h3&amp;gt; --&gt;&lt;h3 id="toc5"&gt;&lt;a name="x18 Equal Divisions of the Octave-Useful Moment-of-Symmetry Scales-Hexatonic:"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:10 --&gt;Hexatonic:&lt;/h3&gt;
&lt;!-- ws:start:WikiTextHeadingRule:12:&amp;lt;h3&amp;gt; --&gt;&lt;h3 id="toc6"&gt;&lt;a name="x18 Equal Divisions of the Octave-Useful Moment-of-Symmetry Scales-Hexatonic:"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:12 --&gt;Hexatonic:&lt;/h3&gt;
  Whole-Tone Scale: 3 3 3 3 3 3&lt;br /&gt;
  Whole-Tone Scale: 3 3 3 3 3 3&lt;br /&gt;
Bicycle: 4 4 1 4 4 1&lt;br /&gt;
Bicycle: 4 4 1 4 4 1&lt;br /&gt;
Rice Hexatonic: 2 5 2 2 5 2&lt;br /&gt;
Rice Hexatonic: 2 5 2 2 5 2&lt;br /&gt;
&lt;!-- ws:start:WikiTextHeadingRule:12:&amp;lt;h3&amp;gt; --&gt;&lt;h3 id="toc6"&gt;&lt;a name="x18 Equal Divisions of the Octave-Useful Moment-of-Symmetry Scales-Heptatonic:"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:12 --&gt;Heptatonic:&lt;/h3&gt;
&lt;!-- ws:start:WikiTextHeadingRule:14:&amp;lt;h3&amp;gt; --&gt;&lt;h3 id="toc7"&gt;&lt;a name="x18 Equal Divisions of the Octave-Useful Moment-of-Symmetry Scales-Heptatonic:"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:14 --&gt;Heptatonic:&lt;/h3&gt;
  Amity/Mish Heptatonic: 3 2 3 2 3 3 2&lt;br /&gt;
  Amity/Mish Heptatonic: 3 2 3 2 3 3 2&lt;br /&gt;
&lt;!-- ws:start:WikiTextHeadingRule:14:&amp;lt;h3&amp;gt; --&gt;&lt;h3 id="toc7"&gt;&lt;a name="x18 Equal Divisions of the Octave-Useful Moment-of-Symmetry Scales-Octatonic:"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:14 --&gt;Octatonic:&lt;/h3&gt;
&lt;!-- ws:start:WikiTextHeadingRule:16:&amp;lt;h3&amp;gt; --&gt;&lt;h3 id="toc8"&gt;&lt;a name="x18 Equal Divisions of the Octave-Useful Moment-of-Symmetry Scales-Octatonic:"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:16 --&gt;Octatonic:&lt;/h3&gt;
  Father Octatonic: 3 1 3 3 1 3 3 1&lt;br /&gt;
  Father Octatonic: 3 1 3 3 1 3 3 1&lt;br /&gt;
Rice Octatonic: 2 2 3 2 2 2 3 2&lt;br /&gt;
Rice Octatonic: 2 2 3 2 2 2 3 2&lt;br /&gt;
&lt;!-- ws:start:WikiTextHeadingRule:16:&amp;lt;h3&amp;gt; --&gt;&lt;h3 id="toc8"&gt;&lt;a name="x18 Equal Divisions of the Octave-Useful Moment-of-Symmetry Scales-Decatonic:"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:16 --&gt;Decatonic:&lt;/h3&gt;
&lt;!-- ws:start:WikiTextHeadingRule:18:&amp;lt;h3&amp;gt; --&gt;&lt;h3 id="toc9"&gt;&lt;a name="x18 Equal Divisions of the Octave-Useful Moment-of-Symmetry Scales-Decatonic:"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:18 --&gt;Decatonic:&lt;/h3&gt;
  Biggie Decatonic: 2 2 1 2 2 2 2 1 2 2&lt;br /&gt;
  Biggie Decatonic: 2 2 1 2 2 2 2 1 2 2&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
&lt;!-- ws:start:WikiTextHeadingRule:18:&amp;lt;h2&amp;gt; --&gt;&lt;h2 id="toc9"&gt;&lt;a name="x18 Equal Divisions of the Octave-Application to Guitar"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:18 --&gt;Application to Guitar&lt;/h2&gt;
&lt;!-- ws:start:WikiTextHeadingRule:20:&amp;lt;h2&amp;gt; --&gt;&lt;h2 id="toc10"&gt;&lt;a name="x18 Equal Divisions of the Octave-Application to Guitar"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:20 --&gt;Application to Guitar&lt;/h2&gt;
  18-EDO is an ideal scale for the first-time refretter, because you can retain all the even-number frets from 12-tET--essentially 1/3 of your work is done for you!&lt;br /&gt;
  18-EDO is an ideal scale for the first-time refretter, because you can retain all the even-number frets from 12-tET--essentially 1/3 of your work is done for you!&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
The &amp;quot;Father Octatonic&amp;quot; scale maps very simply to a 6-string guitar tuned in &amp;quot;reverse-standard&amp;quot; tuning (tune using four 466.667¢ intervals, with one 533.333¢ interval between the 2nd and 3rd strings), making for a softer learning-curve than EDOs like 14, 16, or 21.&lt;/body&gt;&lt;/html&gt;</pre></div>
The &amp;quot;Father Octatonic&amp;quot; scale maps very simply to a 6-string guitar tuned in &amp;quot;reverse-standard&amp;quot; tuning (tune using four 466.667¢ intervals, with one 533.333¢ interval between the 2nd and 3rd strings), making for a softer learning-curve than EDOs like 14, 16, or 21.&lt;/body&gt;&lt;/html&gt;</pre></div>