81/80: Difference between revisions
Wikispaces>xenwolf **Imported revision 356192364 - Original comment: 81/80 highlighted** |
Wikispaces>genewardsmith **Imported revision 514493824 - 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: | : This revision was by author [[User:genewardsmith|genewardsmith]] and made on <tt>2014-06-20 01:02:42 UTC</tt>.<br> | ||
: The original revision id was <tt> | : The original revision id was <tt>514493824</tt>.<br> | ||
: The revision comment was: <tt> | : 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> | ||
<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">The **syntonic** or **Didymus comma** (frequency ratio **81/80**) is the smallest [[superparticular|superparticular interval]] which belongs to the [[5-limit]]. Like [[16_15|16/15]], [[625_624|625/624]], [[2401_2400|2401/2400]] and [[4096_4095|4096/4095]] it has a fourth power as a numerator, | <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">The **syntonic** or **Didymus comma** (frequency ratio **81/80**) is the smallest [[superparticular|superparticular interval]] which belongs to the [[5-limit]]. Like [[16_15|16/15]], [[625_624|625/624]], [[2401_2400|2401/2400]] and [[4096_4095|4096/4095]] it has a fourth power as a numerator. Fourth powers are squares, and any comma with a square numerator is the ratio between two larger successive superparticular intervals; it is in fact the difference between [[10_9|10/9]] and [[9_8|9/8]], the product of which is the just major third, [[5_4|5/4]]. That the numerator is a fourth power entails that the larger of these two intervals itself has a square numerator; 9/8 is the interval between the successive superparticulars 4/3 and 3/2. Tempering it out gives a tuning for the whole tone which is intermediate between 10/9 and 9/8, and leads to [[Meantone family|meantone temperament]]. | ||
Youtube video of "[[http://www.youtube.com/watch?v=IpWiEWFRGAY|Five senses of 81/80]]", demonstratory video by Jacob Barton. | Youtube video of "[[http://www.youtube.com/watch?v=IpWiEWFRGAY|Five senses of 81/80]]", demonstratory video by Jacob Barton. | ||
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[[http://en.wikipedia.org/wiki/Syntonic_comma]]</pre></div> | [[http://en.wikipedia.org/wiki/Syntonic_comma]]</pre></div> | ||
<h4>Original HTML content:</h4> | <h4>Original HTML 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;width:200%;white-space: pre-wrap ! important" class="old-revision-html"><html><head><title>81_80</title></head><body>The <strong>syntonic</strong> or <strong>Didymus comma</strong> (frequency ratio <strong>81/80</strong>) is the smallest <a class="wiki_link" href="/superparticular">superparticular interval</a> which belongs to the <a class="wiki_link" href="/5-limit">5-limit</a>. Like <a class="wiki_link" href="/16_15">16/15</a>, <a class="wiki_link" href="/625_624">625/624</a>, <a class="wiki_link" href="/2401_2400">2401/2400</a> and <a class="wiki_link" href="/4096_4095">4096/4095</a> it has a fourth power as a numerator, | <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"><html><head><title>81_80</title></head><body>The <strong>syntonic</strong> or <strong>Didymus comma</strong> (frequency ratio <strong>81/80</strong>) is the smallest <a class="wiki_link" href="/superparticular">superparticular interval</a> which belongs to the <a class="wiki_link" href="/5-limit">5-limit</a>. Like <a class="wiki_link" href="/16_15">16/15</a>, <a class="wiki_link" href="/625_624">625/624</a>, <a class="wiki_link" href="/2401_2400">2401/2400</a> and <a class="wiki_link" href="/4096_4095">4096/4095</a> it has a fourth power as a numerator. Fourth powers are squares, and any comma with a square numerator is the ratio between two larger successive superparticular intervals; it is in fact the difference between <a class="wiki_link" href="/10_9">10/9</a> and <a class="wiki_link" href="/9_8">9/8</a>, the product of which is the just major third, <a class="wiki_link" href="/5_4">5/4</a>. That the numerator is a fourth power entails that the larger of these two intervals itself has a square numerator; 9/8 is the interval between the successive superparticulars 4/3 and 3/2. Tempering it out gives a tuning for the whole tone which is intermediate between 10/9 and 9/8, and leads to <a class="wiki_link" href="/Meantone%20family">meantone temperament</a>.<br /> | ||
<br /> | <br /> | ||
Youtube video of &quot;<a class="wiki_link_ext" href="http://www.youtube.com/watch?v=IpWiEWFRGAY" rel="nofollow">Five senses of 81/80</a>&quot;, demonstratory video by Jacob Barton.<br /> | Youtube video of &quot;<a class="wiki_link_ext" href="http://www.youtube.com/watch?v=IpWiEWFRGAY" rel="nofollow">Five senses of 81/80</a>&quot;, demonstratory video by Jacob Barton.<br /> |