27edo

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Revision as of 16:02, 13 March 2011 by Wikispaces>Osmiorisbendi (**Imported revision 210042652 - Original comment: **)
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IMPORTED REVISION FROM WIKISPACES

This is an imported revision from Wikispaces. The revision metadata is included below for reference:

This revision was by author Osmiorisbendi and made on 2011-03-13 16:02:35 UTC.
The original revision id was 210042652.
The revision comment was:

The revision contents are below, presented both in the original Wikispaces Wikitext format, and in HTML exactly as Wikispaces rendered it.

Original Wikitext content:

=<span style="color: #0061ff; font-size: 103%;">27 tone equal tempertament</span>= 

If octaves are kept pure, 27edo divides the octave in 27 equal parts each exactly 44.444... cents in size. However, 27 is a prime candidate for octave shrinking, and a step size of 44.3 to 44.35 cents would be reasonable. The reason for this is that 27edo tunes the third, fifth and 7/4 sharply.

Assuming however pure octaves, 27 has a fifth sharp by slightly more than nine cents and a 7/4 sharp by slightly less, and the same 400 cent major third as 12edo, sharp 13 2/3 cents. The result is that 6/5, 7/5 and especially 7/6 are all tuned more accurately than this.

27edo, with its 400 cent major third, tempers out the diesis of 128/125, and also the septimal comma, 64/63 (and hence 126/125 also.) These it shares with 12edo, making some relationships familiar, and as a consequence they both support augene temperament. It shares with 22edo tempering out 245/243 (allegedly a Bohlen-Pierce comma, yet hear it turns up anyway) as well as 64/63, so that they both support superpyth temperament, with quite sharp "superpythagorean" fifths giving a sharp 
9/7 in place of meantone's 5/4.

==Intervals== 
|| Degrees of 27-EDO || Cents value ||
|| 0 || 0 ||
|| 1 || 44,44 ||
|| 2 || 88,89 ||
|| 3 || 133,33 ||
|| 4 || 177,78 ||
|| 5 || 222,22 ||
|| 6 || 266,67 ||
|| 7 || 311,11 ||
|| 8 || 355,56 ||
|| 9 || 400 ||
|| 10 || 444,44 ||
|| 11 || 488,89 ||
|| 12 || 533,33 ||
|| 13 || 577,78 ||
|| 14 || 622,22 ||
|| 15 || 666,67 ||
|| 16 || 711,11 ||
|| 17 || 755,56 ||
|| 18 || 800 ||
|| 19 || 844,44 ||
|| 20 || 888,89 ||
|| 21 || 933,33 ||
|| 22 || 977,78 ||
|| 23 || 1022,22 ||
|| 24 || 1066,67 ||
|| 25 || 1111,11 ||
|| 26 || 1155,56 ||

Original HTML content:

<html><head><title>27edo</title></head><body><!-- ws:start:WikiTextHeadingRule:0:&lt;h1&gt; --><h1 id="toc0"><a name="x27 tone equal tempertament"></a><!-- ws:end:WikiTextHeadingRule:0 --><span style="color: #0061ff; font-size: 103%;">27 tone equal tempertament</span></h1>
 <br />
If octaves are kept pure, 27edo divides the octave in 27 equal parts each exactly 44.444... cents in size. However, 27 is a prime candidate for octave shrinking, and a step size of 44.3 to 44.35 cents would be reasonable. The reason for this is that 27edo tunes the third, fifth and 7/4 sharply.<br />
<br />
Assuming however pure octaves, 27 has a fifth sharp by slightly more than nine cents and a 7/4 sharp by slightly less, and the same 400 cent major third as 12edo, sharp 13 2/3 cents. The result is that 6/5, 7/5 and especially 7/6 are all tuned more accurately than this.<br />
<br />
27edo, with its 400 cent major third, tempers out the diesis of 128/125, and also the septimal comma, 64/63 (and hence 126/125 also.) These it shares with 12edo, making some relationships familiar, and as a consequence they both support augene temperament. It shares with 22edo tempering out 245/243 (allegedly a Bohlen-Pierce comma, yet hear it turns up anyway) as well as 64/63, so that they both support superpyth temperament, with quite sharp &quot;superpythagorean&quot; fifths giving a sharp <br />
9/7 in place of meantone's 5/4.<br />
<br />
<!-- ws:start:WikiTextHeadingRule:2:&lt;h2&gt; --><h2 id="toc1"><a name="x27 tone equal tempertament-Intervals"></a><!-- ws:end:WikiTextHeadingRule:2 -->Intervals</h2>
 

<table class="wiki_table">
    <tr>
        <td>Degrees of 27-EDO<br />
</td>
        <td>Cents value<br />
</td>
    </tr>
    <tr>
        <td>0<br />
</td>
        <td>0<br />
</td>
    </tr>
    <tr>
        <td>1<br />
</td>
        <td>44,44<br />
</td>
    </tr>
    <tr>
        <td>2<br />
</td>
        <td>88,89<br />
</td>
    </tr>
    <tr>
        <td>3<br />
</td>
        <td>133,33<br />
</td>
    </tr>
    <tr>
        <td>4<br />
</td>
        <td>177,78<br />
</td>
    </tr>
    <tr>
        <td>5<br />
</td>
        <td>222,22<br />
</td>
    </tr>
    <tr>
        <td>6<br />
</td>
        <td>266,67<br />
</td>
    </tr>
    <tr>
        <td>7<br />
</td>
        <td>311,11<br />
</td>
    </tr>
    <tr>
        <td>8<br />
</td>
        <td>355,56<br />
</td>
    </tr>
    <tr>
        <td>9<br />
</td>
        <td>400<br />
</td>
    </tr>
    <tr>
        <td>10<br />
</td>
        <td>444,44<br />
</td>
    </tr>
    <tr>
        <td>11<br />
</td>
        <td>488,89<br />
</td>
    </tr>
    <tr>
        <td>12<br />
</td>
        <td>533,33<br />
</td>
    </tr>
    <tr>
        <td>13<br />
</td>
        <td>577,78<br />
</td>
    </tr>
    <tr>
        <td>14<br />
</td>
        <td>622,22<br />
</td>
    </tr>
    <tr>
        <td>15<br />
</td>
        <td>666,67<br />
</td>
    </tr>
    <tr>
        <td>16<br />
</td>
        <td>711,11<br />
</td>
    </tr>
    <tr>
        <td>17<br />
</td>
        <td>755,56<br />
</td>
    </tr>
    <tr>
        <td>18<br />
</td>
        <td>800<br />
</td>
    </tr>
    <tr>
        <td>19<br />
</td>
        <td>844,44<br />
</td>
    </tr>
    <tr>
        <td>20<br />
</td>
        <td>888,89<br />
</td>
    </tr>
    <tr>
        <td>21<br />
</td>
        <td>933,33<br />
</td>
    </tr>
    <tr>
        <td>22<br />
</td>
        <td>977,78<br />
</td>
    </tr>
    <tr>
        <td>23<br />
</td>
        <td>1022,22<br />
</td>
    </tr>
    <tr>
        <td>24<br />
</td>
        <td>1066,67<br />
</td>
    </tr>
    <tr>
        <td>25<br />
</td>
        <td>1111,11<br />
</td>
    </tr>
    <tr>
        <td>26<br />
</td>
        <td>1155,56<br />
</td>
    </tr>
</table>

</body></html>