Golden ratio: Difference between revisions

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**Imported revision 479296358 - Original comment: **
 
Wikispaces>spt3125
**Imported revision 479297806 - 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:spt3125|spt3125]] and made on <tt>2013-12-24 18:33:32 UTC</tt>.<br>
: This revision was by author [[User:spt3125|spt3125]] and made on <tt>2013-12-24 19:03:47 UTC</tt>.<br>
: The original revision id was <tt>479296358</tt>.<br>
: The original revision id was <tt>479297806</tt>.<br>
: The revision comment was: <tt></tt><br>
: 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>
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&lt;span class="Unicode"&gt;As the ratios of successive terms of the Fibonacci sequence converge on phi, the just intonation intervals 3/2, 5/3, 8/5, 13/8, 21/13, ... converge on ~833.1 cents.&lt;/span&gt;
&lt;span class="Unicode"&gt;As the ratios of successive terms of the Fibonacci sequence converge on phi, the just intonation intervals 3/2, 5/3, 8/5, 13/8, 21/13, ... converge on ~833.1 cents.&lt;/span&gt;


"Logarithmic phi", or 1200*&lt;span class="Unicode"&gt;ϕ cents = 1941.6 cents (or, octave-reduced, 741.6 cents) is also useful.&lt;/span&gt;
"Logarithmic phi", or 1200*&lt;span class="Unicode"&gt;ϕ cents = 1941.6 cents (or, octave-reduced, 741.6 cents) is also useful as a generator, for example in [[Erv Wilson]]'s "Golden Horagrams".&lt;/span&gt;




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[[xenharmonic/833 Cent Golden Scale (Bohlen)|833 Cent ]]&lt;span class="w_hl"&gt;[[xenharmonic/833 Cent Golden Scale (Bohlen)|Golden]]&lt;/span&gt;[[xenharmonic/833 Cent Golden Scale (Bohlen)| Scale (Bohlen) ]]
[[xenharmonic/833 Cent Golden Scale (Bohlen)|833 Cent ]]&lt;span class="w_hl"&gt;[[xenharmonic/833 Cent Golden Scale (Bohlen)|Golden]]&lt;/span&gt;[[xenharmonic/833 Cent Golden Scale (Bohlen)| Scale (Bohlen) ]]


[[@http://dkeenan.com/Music/NobleMediant.txt|The Noble Mediant: Complex ratios and metastable musical intervals]], by [[Margo Schulter]] and [[David Keenan]]</pre></div>
[[@http://dkeenan.com/Music/NobleMediant.txt|The Noble Mediant: Complex ratios and metastable musical intervals]], by [[Margo Schulter]] and [[Dave Keenan|David Keenan]]
 
[[@http://www.elvenminstrel.com/music/tuning/horagrams/horagram_intro.htm|5- to 9-tone, octave-repeating scales from Wilson's Golden Horagrams of the Scale Tree]], by David Finnamore</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">&lt;html&gt;&lt;head&gt;&lt;title&gt;Golden Ratio&lt;/title&gt;&lt;/head&gt;&lt;body&gt;&lt;!-- ws:start:WikiTextHeadingRule:0:&amp;lt;h2&amp;gt; --&gt;&lt;h2 id="toc0"&gt;&lt;a name="x-Introduction"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:0 --&gt;Introduction&lt;/h2&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;Golden Ratio&lt;/title&gt;&lt;/head&gt;&lt;body&gt;&lt;!-- ws:start:WikiTextHeadingRule:0:&amp;lt;h2&amp;gt; --&gt;&lt;h2 id="toc0"&gt;&lt;a name="x-Introduction"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:0 --&gt;Introduction&lt;/h2&gt;
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&lt;span class="Unicode"&gt;As the ratios of successive terms of the Fibonacci sequence converge on phi, the just intonation intervals 3/2, 5/3, 8/5, 13/8, 21/13, ... converge on ~833.1 cents.&lt;/span&gt;&lt;br /&gt;
&lt;span class="Unicode"&gt;As the ratios of successive terms of the Fibonacci sequence converge on phi, the just intonation intervals 3/2, 5/3, 8/5, 13/8, 21/13, ... converge on ~833.1 cents.&lt;/span&gt;&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
&amp;quot;Logarithmic phi&amp;quot;, or 1200*&lt;span class="Unicode"&gt;ϕ cents = 1941.6 cents (or, octave-reduced, 741.6 cents) is also useful.&lt;/span&gt;&lt;br /&gt;
&amp;quot;Logarithmic phi&amp;quot;, or 1200*&lt;span class="Unicode"&gt;ϕ cents = 1941.6 cents (or, octave-reduced, 741.6 cents) is also useful as a generator, for example in &lt;a class="wiki_link" href="/Erv%20Wilson"&gt;Erv Wilson&lt;/a&gt;'s &amp;quot;Golden Horagrams&amp;quot;.&lt;/span&gt;&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
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&lt;a class="wiki_link" href="http://xenharmonic.wikispaces.com/833%20Cent%20Golden%20Scale%20%28Bohlen%29"&gt;833 Cent &lt;/a&gt;&lt;span class="w_hl"&gt;&lt;a class="wiki_link" href="http://xenharmonic.wikispaces.com/833%20Cent%20Golden%20Scale%20%28Bohlen%29"&gt;Golden&lt;/a&gt;&lt;/span&gt;&lt;a class="wiki_link" href="http://xenharmonic.wikispaces.com/833%20Cent%20Golden%20Scale%20%28Bohlen%29"&gt; Scale (Bohlen) &lt;/a&gt;&lt;br /&gt;
&lt;a class="wiki_link" href="http://xenharmonic.wikispaces.com/833%20Cent%20Golden%20Scale%20%28Bohlen%29"&gt;833 Cent &lt;/a&gt;&lt;span class="w_hl"&gt;&lt;a class="wiki_link" href="http://xenharmonic.wikispaces.com/833%20Cent%20Golden%20Scale%20%28Bohlen%29"&gt;Golden&lt;/a&gt;&lt;/span&gt;&lt;a class="wiki_link" href="http://xenharmonic.wikispaces.com/833%20Cent%20Golden%20Scale%20%28Bohlen%29"&gt; Scale (Bohlen) &lt;/a&gt;&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
&lt;a class="wiki_link_ext" href="http://dkeenan.com/Music/NobleMediant.txt" rel="nofollow" target="_blank"&gt;The Noble Mediant: Complex ratios and metastable musical intervals&lt;/a&gt;, by &lt;a class="wiki_link" href="/Margo%20Schulter"&gt;Margo Schulter&lt;/a&gt; and &lt;a class="wiki_link" href="/David%20Keenan"&gt;David Keenan&lt;/a&gt;&lt;/body&gt;&lt;/html&gt;</pre></div>
&lt;a class="wiki_link_ext" href="http://dkeenan.com/Music/NobleMediant.txt" rel="nofollow" target="_blank"&gt;The Noble Mediant: Complex ratios and metastable musical intervals&lt;/a&gt;, by &lt;a class="wiki_link" href="/Margo%20Schulter"&gt;Margo Schulter&lt;/a&gt; and &lt;a class="wiki_link" href="/Dave%20Keenan"&gt;David Keenan&lt;/a&gt;&lt;br /&gt;
&lt;br /&gt;
&lt;a class="wiki_link_ext" href="http://www.elvenminstrel.com/music/tuning/horagrams/horagram_intro.htm" rel="nofollow" target="_blank"&gt;5- to 9-tone, octave-repeating scales from Wilson's Golden Horagrams of the Scale Tree&lt;/a&gt;, by David Finnamore&lt;/body&gt;&lt;/html&gt;</pre></div>

Revision as of 19:03, 24 December 2013

IMPORTED REVISION FROM WIKISPACES

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

This revision was by author spt3125 and made on 2013-12-24 19:03:47 UTC.
The original revision id was 479297806.
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:

==Introduction== 

The "golden ratio" or "phi" (Greek letter Φ / φ / <span class="Unicode">ϕ ) may be defined by a/b such that a/b = (a+b)/a. It follows that ϕ</span>-1 = 1/<span class="Unicode">ϕ, and also that ϕ = (1+sqrt(5))/2, or approximately </span>1.6180339887... <span class="Unicode">ϕ is an irrational number that appears in many branches of mathematics.</span>

[[@http://en.wikipedia.org/wiki/Golden_ratio|Wikipedia article on phi]]


==Musical applications== 

<span class="Unicode">Phi taken as a musical ratio (ϕ</span>*f where f=1/1) <span class="Unicode">is about 833.1 cents. This is sometimes called "acoustical phi".</span>
<span class="Unicode">As the ratios of successive terms of the Fibonacci sequence converge on phi, the just intonation intervals 3/2, 5/3, 8/5, 13/8, 21/13, ... converge on ~833.1 cents.</span>

"Logarithmic phi", or 1200*<span class="Unicode">ϕ cents = 1941.6 cents (or, octave-reduced, 741.6 cents) is also useful as a generator, for example in [[Erv Wilson]]'s "Golden Horagrams".</span>


==Additional reading== 

<span class="w_hl">[[xenharmonic/Phi as a Generator|Phi]]</span>[[xenharmonic/Phi as a Generator| as a Generator ]]

[[sqrtphi]], a temperament based on the square root of phi (~416.5 cents) as a generator

<span class="w_hl">[[xenharmonic/Golden Meantone|Golden]]</span>[[xenharmonic/Golden Meantone| Meantone ]]

[[xenharmonic/833 Cent Golden Scale (Bohlen)|833 Cent ]]<span class="w_hl">[[xenharmonic/833 Cent Golden Scale (Bohlen)|Golden]]</span>[[xenharmonic/833 Cent Golden Scale (Bohlen)| Scale (Bohlen) ]]

[[@http://dkeenan.com/Music/NobleMediant.txt|The Noble Mediant: Complex ratios and metastable musical intervals]], by [[Margo Schulter]] and [[Dave Keenan|David Keenan]]

[[@http://www.elvenminstrel.com/music/tuning/horagrams/horagram_intro.htm|5- to 9-tone, octave-repeating scales from Wilson's Golden Horagrams of the Scale Tree]], by David Finnamore

Original HTML content:

<html><head><title>Golden Ratio</title></head><body><!-- ws:start:WikiTextHeadingRule:0:&lt;h2&gt; --><h2 id="toc0"><a name="x-Introduction"></a><!-- ws:end:WikiTextHeadingRule:0 -->Introduction</h2>
 <br />
The &quot;golden ratio&quot; or &quot;phi&quot; (Greek letter Φ / φ / <span class="Unicode">ϕ ) may be defined by a/b such that a/b = (a+b)/a. It follows that ϕ</span>-1 = 1/<span class="Unicode">ϕ, and also that ϕ = (1+sqrt(5))/2, or approximately </span>1.6180339887... <span class="Unicode">ϕ is an irrational number that appears in many branches of mathematics.</span><br />
<br />
<a class="wiki_link_ext" href="http://en.wikipedia.org/wiki/Golden_ratio" rel="nofollow" target="_blank">Wikipedia article on phi</a><br />
<br />
<br />
<!-- ws:start:WikiTextHeadingRule:2:&lt;h2&gt; --><h2 id="toc1"><a name="x-Musical applications"></a><!-- ws:end:WikiTextHeadingRule:2 -->Musical applications</h2>
 <br />
<span class="Unicode">Phi taken as a musical ratio (ϕ</span>*f where f=1/1) <span class="Unicode">is about 833.1 cents. This is sometimes called &quot;acoustical phi&quot;.</span><br />
<span class="Unicode">As the ratios of successive terms of the Fibonacci sequence converge on phi, the just intonation intervals 3/2, 5/3, 8/5, 13/8, 21/13, ... converge on ~833.1 cents.</span><br />
<br />
&quot;Logarithmic phi&quot;, or 1200*<span class="Unicode">ϕ cents = 1941.6 cents (or, octave-reduced, 741.6 cents) is also useful as a generator, for example in <a class="wiki_link" href="/Erv%20Wilson">Erv Wilson</a>'s &quot;Golden Horagrams&quot;.</span><br />
<br />
<br />
<!-- ws:start:WikiTextHeadingRule:4:&lt;h2&gt; --><h2 id="toc2"><a name="x-Additional reading"></a><!-- ws:end:WikiTextHeadingRule:4 -->Additional reading</h2>
 <br />
<span class="w_hl"><a class="wiki_link" href="http://xenharmonic.wikispaces.com/Phi%20as%20a%20Generator">Phi</a></span><a class="wiki_link" href="http://xenharmonic.wikispaces.com/Phi%20as%20a%20Generator"> as a Generator </a><br />
<br />
<a class="wiki_link" href="/sqrtphi">sqrtphi</a>, a temperament based on the square root of phi (~416.5 cents) as a generator<br />
<br />
<span class="w_hl"><a class="wiki_link" href="http://xenharmonic.wikispaces.com/Golden%20Meantone">Golden</a></span><a class="wiki_link" href="http://xenharmonic.wikispaces.com/Golden%20Meantone"> Meantone </a><br />
<br />
<a class="wiki_link" href="http://xenharmonic.wikispaces.com/833%20Cent%20Golden%20Scale%20%28Bohlen%29">833 Cent </a><span class="w_hl"><a class="wiki_link" href="http://xenharmonic.wikispaces.com/833%20Cent%20Golden%20Scale%20%28Bohlen%29">Golden</a></span><a class="wiki_link" href="http://xenharmonic.wikispaces.com/833%20Cent%20Golden%20Scale%20%28Bohlen%29"> Scale (Bohlen) </a><br />
<br />
<a class="wiki_link_ext" href="http://dkeenan.com/Music/NobleMediant.txt" rel="nofollow" target="_blank">The Noble Mediant: Complex ratios and metastable musical intervals</a>, by <a class="wiki_link" href="/Margo%20Schulter">Margo Schulter</a> and <a class="wiki_link" href="/Dave%20Keenan">David Keenan</a><br />
<br />
<a class="wiki_link_ext" href="http://www.elvenminstrel.com/music/tuning/horagrams/horagram_intro.htm" rel="nofollow" target="_blank">5- to 9-tone, octave-repeating scales from Wilson's Golden Horagrams of the Scale Tree</a>, by David Finnamore</body></html>