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<h2>IMPORTED REVISION FROM WIKISPACES</h2>
== Assumptions ==
This is an imported revision from Wikispaces. The revision metadata is included below for reference:<br>
Assume, for now, that a rhythm is specified as a set of pulses within an interval of time. Assume that a pulse is an instant of attack. Call the total interval of time a ''period''. '''Cyclical rhythms'' as defined here are distinguished by the exact spacing of pulses within a period; the tempo or tempo change of the period is not (yet) relevant to the cyclical rhythm. In our examples, the magnitude of the duration of the period will remain fixed.
: This revision was by author [[User:xenjacob|xenjacob]] and made on <tt>2009-01-21 10:31:01 UTC</tt>.<br>
: The original revision id was <tt>54254194</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>
<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">=Assumptions=  
Assume, for now, that a rhythm is specified as a set of pulses within an interval of time. Assume that a pulse is an instant of attack. Call the total interval of time a //period//. 'Cyclyclical rhythms' as defined here are distinguished by the exact spacing of pulses within a period; the tempo or tempo change of the period is not (yet) relevant to the cyclyclical rhythm. In our examples, the magnitude of the duration of the period will remain fixed.


The durations in cyclyclical rhythms are specified not in //absolute// terms of time interval (minutes, seconds, beats of a metronome), but //relative// to the period, and thus expressed as a (unitless) proportion. For example, '1/2' (or '0.5') will represent a duration (interval of time) of exactly half the duration of the period.
The durations in cyclical rhythms are specified not in ''absolute'' terms of time interval (minutes, seconds, beats of a metronome), but ''relative'' to the period, and thus expressed as a (unitless) proportion. For example, '1/2' (or '0.5') will represent a duration (interval of time) of exactly half the duration of the period.


We are concerned with durations that are shorter than the duration of the period; i.e., greater than or equal to zero (no interval) and less than one (period). We can easily convert numbers outside that range by adding or subtracting 1 until they are in the range. This is tantamount to using a [[http://en.wikipedia.org/wiki/Modular_arithmetic|Modular arithmetic]] with a modulus of 1. (Clocks and twelve-tone theory use a modulus of 12.)
We are concerned with durations that are shorter than the duration of the period; i.e., greater than or equal to zero (no interval) and less than one (period). We can easily convert numbers outside that range by adding or subtracting 1 until they are in the range. This is tantamount to using a [https://en.wikipedia.org/wiki/Modular_arithmetic Modular arithmetic] with a modulus of 1. (Clocks and twelve-tone theory use a modulus of 12.)


We can use the metaphor of a timeline, assuming that a line segment (representing a period) can be broken up into smaller line segments (durations or intervals) as delineated by the placement of points (pulses):
We can use the metaphor of a timeline, assuming that a line segment (representing a period) can be broken up into smaller line segments (durations or intervals) as delineated by the placement of points (pulses):


[[image:mr_line.png align="center"]]
[[File:mr_line.png|alt=mr_line.png|mr_line.png]]Furthermore, we can emphasize the cyclical nature of our arithmetic if we bend the line segment into a circle (drawing a point at the top for 0/1):
Furthermore, we can emphasize the cyclical nature of our arithmetic if we bend the line segment into a circle (drawing a point at the top for 0/1):
 
[[image:mr_cycle.png align="center"]]
[[File:mr_cycle.png|alt=mr_cycle.png|mr_cycle.png]]When we want to refer to an interval ''from zero'', which also specifies a single pulse within a period, we will use unadorned expressions (e.g. ''a'' and ''1-a''). When we want to talk about an interval ''from anywhere'', emphasizing only the magnitude of it, we will enclose it within vertical slashes | |  
When we want to refer to an interval //from zero//, which also specifies a single pulse within a period, we will use unadorned expressions (e.g. //a// and //1-a//). When we want to talk about an interval //from anywhere//, emphasizing only the magnitude of it, we will enclose it within vertical slashes | |  
 
=Generators=  
== Generators ==
Cyclyclical rhythms are calculated by taking //multiples// of a single interval, called the //generating interval// or //generator//. When one interval is called a //generator// interval relative to a period, a //family// of cyclyclical rhythms is specified. When how many multiples and which multiples are specified, a single cyclyclical rhythm is specified.</pre></div>
Cyclical rhythms are calculated by taking ''multiples'' of a single interval, called the ''generating interval'' or ''generator''. When one interval is called a ''generator'' interval relative to a period, a ''family'' of cyclical rhythms is specified. When how many multiples and which multiples are specified, a single cyclical rhythm is specified.
<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;MOS Rhythm Tutorial&lt;/title&gt;&lt;/head&gt;&lt;body&gt;&lt;!-- ws:start:WikiTextHeadingRule:0:&amp;lt;h1&amp;gt; --&gt;&lt;h1 id="toc0"&gt;&lt;a name="Assumptions"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:0 --&gt;Assumptions&lt;/h1&gt;
== History ==
Assume, for now, that a rhythm is specified as a set of pulses within an interval of time. Assume that a pulse is an instant of attack. Call the total interval of time a &lt;em&gt;period&lt;/em&gt;. 'Cyclyclical rhythms' as defined here are distinguished by the exact spacing of pulses within a period; the tempo or tempo change of the period is not (yet) relevant to the cyclyclical rhythm. In our examples, the magnitude of the duration of the period will remain fixed.&lt;br /&gt;
David Canright was the first to suggest Fibonacci Rhythms in 1/1. This led to Kraig Grady to be the first to apply MOS patterns to rhythms. Two papers on the subject can be found here:
&lt;br /&gt;
 
The durations in cyclyclical rhythms are specified not in &lt;em&gt;absolute&lt;/em&gt; terms of time interval (minutes, seconds, beats of a metronome), but &lt;em&gt;relative&lt;/em&gt; to the period, and thus expressed as a (unitless) proportion. For example, '1/2' (or '0.5') will represent a duration (interval of time) of exactly half the duration of the period.&lt;br /&gt;
* [http://anaphoria.com/hora.pdf A Rhythmic Application of the Horagrams] from ''[[Xenharmonikon]] 16''
&lt;br /&gt;
* [http://anaphoria.com/horo2.pdf More on Horogram Rhythms]
We are concerned with durations that are shorter than the duration of the period; i.e., greater than or equal to zero (no interval) and less than one (period). We can easily convert numbers outside that range by adding or subtracting 1 until they are in the range. This is tantamount to using a &lt;a class="wiki_link_ext" href="http://en.wikipedia.org/wiki/Modular_arithmetic" rel="nofollow"&gt;Modular arithmetic&lt;/a&gt; with a modulus of 1. (Clocks and twelve-tone theory use a modulus of 12.)&lt;br /&gt;
 
&lt;br /&gt;
[[Category:Non-scale applications of MOS]]
We can use the metaphor of a timeline, assuming that a line segment (representing a period) can be broken up into smaller line segments (durations or intervals) as delineated by the placement of points (pulses):&lt;br /&gt;
[[Category:Rhythm]]
&lt;br /&gt;
[[Category:todo:expand]]
&lt;!-- ws:start:WikiTextLocalImageRule:4:&amp;lt;div style=&amp;quot;text-align: center&amp;quot;&amp;gt;&amp;lt;img src=&amp;quot;/file/view/mr_line.png/54241800/mr_line.png&amp;quot; alt=&amp;quot;&amp;quot; title=&amp;quot;&amp;quot; /&amp;gt;&amp;lt;/div&amp;gt; --&gt;&lt;div style="text-align: center"&gt;&lt;img src="/file/view/mr_line.png/54241800/mr_line.png" alt="mr_line.png" title="mr_line.png" /&gt;&lt;/div&gt;&lt;!-- ws:end:WikiTextLocalImageRule:4 --&gt;Furthermore, we can emphasize the cyclical nature of our arithmetic if we bend the line segment into a circle (drawing a point at the top for 0/1):&lt;br /&gt;
 
&lt;!-- ws:start:WikiTextLocalImageRule:5:&amp;lt;div style=&amp;quot;text-align: center&amp;quot;&amp;gt;&amp;lt;img src=&amp;quot;/file/view/mr_cycle.png/54241802/mr_cycle.png&amp;quot; alt=&amp;quot;&amp;quot; title=&amp;quot;&amp;quot; /&amp;gt;&amp;lt;/div&amp;gt; --&gt;&lt;div style="text-align: center"&gt;&lt;img src="/file/view/mr_cycle.png/54241802/mr_cycle.png" alt="mr_cycle.png" title="mr_cycle.png" /&gt;&lt;/div&gt;&lt;!-- ws:end:WikiTextLocalImageRule:5 --&gt;When we want to refer to an interval &lt;em&gt;from zero&lt;/em&gt;, which also specifies a single pulse within a period, we will use unadorned expressions (e.g. &lt;em&gt;a&lt;/em&gt; and &lt;em&gt;1-a&lt;/em&gt;). When we want to talk about an interval &lt;em&gt;from anywhere&lt;/em&gt;, emphasizing only the magnitude of it, we will enclose it within vertical slashes | | &lt;br /&gt;
== See also ==
&lt;!-- ws:start:WikiTextHeadingRule:2:&amp;lt;h1&amp;gt; --&gt;&lt;h1 id="toc1"&gt;&lt;a name="Generators"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:2 --&gt;Generators&lt;/h1&gt;
 
Cyclyclical rhythms are calculated by taking &lt;em&gt;multiples&lt;/em&gt; of a single interval, called the &lt;em&gt;generating interval&lt;/em&gt; or &lt;em&gt;generator&lt;/em&gt;. When one interval is called a &lt;em&gt;generator&lt;/em&gt; interval relative to a period, a &lt;em&gt;family&lt;/em&gt; of cyclyclical rhythms is specified. When how many multiples and which multiples are specified, a single cyclyclical rhythm is specified.&lt;/body&gt;&lt;/html&gt;</pre></div>
* [[Gallery of MOS patterns]]