Magic comma: Difference between revisions

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<h2>IMPORTED REVISION FROM WIKISPACES</h2>
{{Infobox Interval
This is an imported revision from Wikispaces. The revision metadata is included below for reference:<br>
| Ratio = 3125/3072
: This revision was by author [[User:genewardsmith|genewardsmith]] and made on <tt>2011-10-24 15:31:48 UTC</tt>.<br>
| Name = magic comma, small diesis
: The original revision id was <tt>268058106</tt>.<br>
| Color name = Ly<sup>5</sup>-2, Laquinyo comma
: The revision comment was: <tt></tt><br>
| Comma = yes
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>
 
<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 magic comma or small diesis is the interval 3125/3072 of 29.614 cents. It is the amount by which five major thirds exceeds the twelfth, or "tritave"; in other words (5/4)^5/3. Tempering it out leads to 5-limit [[Magic family|magic temperament]], also known as astrology.</pre></div>
The '''magic comma''' or '''small diesis''' is the interval '''3125/3072'''. It is the amount by which five major thirds ([[5/4]]) exceeds the twelfth, or ''[[tritave]]''; in other words (5/4)<sup>5</sup>/3, the amount by which two chromatic semitones of 25/24 exceed a diatonic semitone of 16/15, and the amount by which 25/24 exceeds the lesser diesis of [[128/125]].
<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">&lt;html&gt;&lt;head&gt;&lt;title&gt;magic comma&lt;/title&gt;&lt;/head&gt;&lt;body&gt;The magic comma or small diesis is the interval 3125/3072 of 29.614 cents. It is the amount by which five major thirds exceeds the twelfth, or &amp;quot;tritave&amp;quot;; in other words (5/4)^5/3. Tempering it out leads to 5-limit &lt;a class="wiki_link" href="/Magic%20family"&gt;magic temperament&lt;/a&gt;, also known as astrology.&lt;/body&gt;&lt;/html&gt;</pre></div>
In 12edo, instead of being tempered out, it is inflated to a whole semitone—five 5/4s make a minor thirteenth (20 steps), while 3/1 is a perfect twelfth (19 steps). Similarly, 25/24 and 16/15 are both mapped to one semitone, making a stack of two 25/24s one semitone larger than 16/15, and 25/24 is mapped to one step while 128/125 is tempered out.
 
== Temperaments ==
Tempering it out leads to [[Magic family #Five-limit magic|5-limit magic temperament]].
 
== See also ==
* [[Magic family]], where it is tempered out
* [[Small comma]]
 
[[Category:Magic]]
[[Category:Commas named for their regular temperament properties]]

Latest revision as of 22:24, 19 March 2025

Interval information
Ratio 3125/3072
Factorization 2-10 × 3-1 × 55
Monzo [-10 -1 5
Size in cents 29.61357¢
Names magic comma,
small diesis
Color name Ly5-2, Laquinyo comma
FJS name [math]\displaystyle{ \text{dd}{-2}^{5,5,5,5,5} }[/math]
Special properties reduced
Tenney height (log2 nd) 23.1946
Weil height (log2 max(n, d)) 23.2193
Wilson height (sopfr(nd)) 48
Comma size small
Open this interval in xen-calc

The magic comma or small diesis is the interval 3125/3072. It is the amount by which five major thirds (5/4) exceeds the twelfth, or tritave; in other words (5/4)5/3, the amount by which two chromatic semitones of 25/24 exceed a diatonic semitone of 16/15, and the amount by which 25/24 exceeds the lesser diesis of 128/125.

In 12edo, instead of being tempered out, it is inflated to a whole semitone—five 5/4s make a minor thirteenth (20 steps), while 3/1 is a perfect twelfth (19 steps). Similarly, 25/24 and 16/15 are both mapped to one semitone, making a stack of two 25/24s one semitone larger than 16/15, and 25/24 is mapped to one step while 128/125 is tempered out.

Temperaments

Tempering it out leads to 5-limit magic temperament.

See also