Interseptimal interval: Difference between revisions

Wikispaces>xenwolf
**Imported revision 574999245 - Original comment: **
Wikispaces>MasonGreen1
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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:xenwolf|xenwolf]] and made on <tt>2016-02-16 16:36:49 UTC</tt>.<br>
: This revision was by author [[User:MasonGreen1|MasonGreen1]] and made on <tt>2016-03-14 01:42:29 UTC</tt>.<br>
: The original revision id was <tt>574999245</tt>.<br>
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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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# Maj6-min7 -- intermediate between 12/7 and 7/4 -- 940¢-960¢
# Maj6-min7 -- intermediate between 12/7 and 7/4 -- 940¢-960¢


Interseptimal intervals are well-represented in [[24edo]] at 250¢, 450¢, 750¢ and 950¢. As they fall in ambiguous zones between simpler categories, they are inevitably xenharmonic.
Interseptimal intervals are well-represented in [[24edo]] at 250¢, 450¢, 750¢ and 950¢. They also appear in [[19edo]] and [[29edo]].
 
As they fall in ambiguous zones between simpler categories, they are inevitably xenharmonic. This also makes them difficult to name: do we classify a 250-cent interval as a second, a third, both, or neither? One option is to give each region a distinct name (analogous to using the word //tritone// rather than diminished fifth or augmented fourth). Possible names that could be used are:
 
# 240¢-260¢ -- semifourth -- an interval of this size is around half the size of a perfect fourth.
# 440¢-468¢ -- semisixth -- an interval of this size is around half the size of a major sixth.
# 732¢-760¢ -- semitenth -- an interval of this size is around half the size of a major tenth (i. e., compound major third). Another possible name is sesquifourth (since this is also about one and a half times the size of a perfect fourth).
# 940¢-960¢ -- semitwelfth -- an interval of this size is around half the size of a perfect twelfth (i e., a compound perfect fifth, or tritave). All even [[edt|edts]] have a semitwelfth of approximately 951 cents, analogous to the 600 cent tritone shared by all even edos.
 
This makes notating these intervals very easy as long as we have an agreed-upon symbol for "semi".
 
By analogy the tritone could also be called a semioctave, although the term tritone is so well-established that seems is little reason to change it now.
 


==Examples==  
==Examples==  
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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;width:200%;white-space: pre-wrap ! important" class="old-revision-html">&lt;html&gt;&lt;head&gt;&lt;title&gt;Interseptimal&lt;/title&gt;&lt;/head&gt;&lt;body&gt;In the theory of &lt;a class="wiki_link" href="/Margo%20Schulter"&gt;Margo Schulter&lt;/a&gt;, &lt;em&gt;interseptimal&lt;/em&gt; is a category of intervals which occupy regions intermediate between two septimal ratios such as &lt;a class="wiki_link" href="/8_7"&gt;8/7&lt;/a&gt; and &lt;a class="wiki_link" href="/7_6"&gt;7/6&lt;/a&gt;, or &lt;a class="wiki_link" href="/12_7"&gt;12/7&lt;/a&gt; and &lt;a class="wiki_link" href="/7_4"&gt;7/4&lt;/a&gt;. There are four interseptimal regions given below, with approximate cents ranges from Schulter's article &lt;a class="wiki_link_ext" href="http://www.bestii.com/%7Emschulter/IntervalSpectrumRegions.txt" rel="nofollow"&gt;Regions of the Interval Spectrum&lt;/a&gt;:&lt;br /&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;Interseptimal&lt;/title&gt;&lt;/head&gt;&lt;body&gt;In the theory of &lt;a class="wiki_link" href="/Margo%20Schulter"&gt;Margo Schulter&lt;/a&gt;, &lt;em&gt;interseptimal&lt;/em&gt; is a category of intervals which occupy regions intermediate between two septimal ratios such as &lt;a class="wiki_link" href="/8_7"&gt;8/7&lt;/a&gt; and &lt;a class="wiki_link" href="/7_6"&gt;7/6&lt;/a&gt;, or &lt;a class="wiki_link" href="/12_7"&gt;12/7&lt;/a&gt; and &lt;a class="wiki_link" href="/7_4"&gt;7/4&lt;/a&gt;. There are four interseptimal regions given below, with approximate cents ranges from Schulter's article &lt;a class="wiki_link_ext" href="http://www.bestii.com/%7Emschulter/IntervalSpectrumRegions.txt" rel="nofollow"&gt;Regions of the Interval Spectrum&lt;/a&gt;:&lt;br /&gt;
&lt;ol&gt;&lt;li&gt;Maj2-min3 -- intermediate between 8/7 and 7/6 -- 240¢-260¢&lt;/li&gt;&lt;li&gt;Maj3-4 -- intermediate between &lt;a class="wiki_link" href="/9_7"&gt;9/7&lt;/a&gt; and &lt;a class="wiki_link" href="/21_16"&gt;21/16&lt;/a&gt; -- 440¢-468¢&lt;/li&gt;&lt;li&gt;5-min6 -- intermediate between &lt;a class="wiki_link" href="/32_21"&gt;32/21&lt;/a&gt; and &lt;a class="wiki_link" href="/14_9"&gt;14/9&lt;/a&gt; -- 732¢-760¢&lt;/li&gt;&lt;li&gt;Maj6-min7 -- intermediate between 12/7 and 7/4 -- 940¢-960¢&lt;/li&gt;&lt;/ol&gt;&lt;br /&gt;
&lt;ol&gt;&lt;li&gt;Maj2-min3 -- intermediate between 8/7 and 7/6 -- 240¢-260¢&lt;/li&gt;&lt;li&gt;Maj3-4 -- intermediate between &lt;a class="wiki_link" href="/9_7"&gt;9/7&lt;/a&gt; and &lt;a class="wiki_link" href="/21_16"&gt;21/16&lt;/a&gt; -- 440¢-468¢&lt;/li&gt;&lt;li&gt;5-min6 -- intermediate between &lt;a class="wiki_link" href="/32_21"&gt;32/21&lt;/a&gt; and &lt;a class="wiki_link" href="/14_9"&gt;14/9&lt;/a&gt; -- 732¢-760¢&lt;/li&gt;&lt;li&gt;Maj6-min7 -- intermediate between 12/7 and 7/4 -- 940¢-960¢&lt;/li&gt;&lt;/ol&gt;&lt;br /&gt;
Interseptimal intervals are well-represented in &lt;a class="wiki_link" href="/24edo"&gt;24edo&lt;/a&gt; at 250¢, 450¢, 750¢ and 950¢. As they fall in ambiguous zones between simpler categories, they are inevitably xenharmonic.&lt;br /&gt;
Interseptimal intervals are well-represented in &lt;a class="wiki_link" href="/24edo"&gt;24edo&lt;/a&gt; at 250¢, 450¢, 750¢ and 950¢. They also appear in &lt;a class="wiki_link" href="/19edo"&gt;19edo&lt;/a&gt; and &lt;a class="wiki_link" href="/29edo"&gt;29edo&lt;/a&gt;.&lt;br /&gt;
&lt;br /&gt;
As they fall in ambiguous zones between simpler categories, they are inevitably xenharmonic. This also makes them difficult to name: do we classify a 250-cent interval as a second, a third, both, or neither? One option is to give each region a distinct name (analogous to using the word &lt;em&gt;tritone&lt;/em&gt; rather than diminished fifth or augmented fourth). Possible names that could be used are:&lt;br /&gt;
&lt;br /&gt;
&lt;ol&gt;&lt;li&gt;240¢-260¢ -- semifourth -- an interval of this size is around half the size of a perfect fourth.&lt;/li&gt;&lt;li&gt;440¢-468¢ -- semisixth -- an interval of this size is around half the size of a major sixth.&lt;/li&gt;&lt;li&gt;732¢-760¢ -- semitenth -- an interval of this size is around half the size of a major tenth (i. e., compound major third). Another possible name is sesquifourth (since this is also about one and a half times the size of a perfect fourth).&lt;/li&gt;&lt;li&gt;940¢-960¢ -- semitwelfth -- an interval of this size is around half the size of a perfect twelfth (i e., a compound perfect fifth, or tritave). All even &lt;a class="wiki_link" href="/edt"&gt;edts&lt;/a&gt; have a semitwelfth of approximately 951 cents, analogous to the 600 cent tritone shared by all even edos.&lt;/li&gt;&lt;/ol&gt;&lt;br /&gt;
This makes notating these intervals very easy as long as we have an agreed-upon symbol for &amp;quot;semi&amp;quot;.&lt;br /&gt;
&lt;br /&gt;
By analogy the tritone could also be called a semioctave, although the term tritone is so well-established that seems is little reason to change it now.&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
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