Frequency ratio: Difference between revisions

Revision as of 20:29, 13 August 2014

IMPORTED REVISION FROM WIKISPACES

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

This revision was by author Omegatron and made on 2014-08-13 20:29:26 UTC.

The original revision id was 518470200.

The revision comment was: can't find any explanation for this notation

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

Original Wikitext content:

A **frequency ratio** is the relationship between the frequencies of two sound waves. For example, a piano string vibrating at 110 Hz (110 times per second) and a piano string vibrating at 220 Hz are in a 2:1 ratio (since 220/110 reduces to 2/1).

Ratios of frequencies may be written several ways:
2/1
2:1
1/2
1:2

When the larger number is written first, this usually signifies a second note being played //above// some base tone (perhaps the starting note of a scale). When the smaller number is written first, this usually signifies the second note being played //below// that base tone.

<span class="wiki_link_ext">The [[http://en.wikipedia.org/wiki/Harmonic_series_%28music%29|harmonic series]] can be represented as a ratio - 1:2:3:4:5:6:7:8:9:10:11:12:13:14:15:16:17... etc.</span>

Chords can also be expressed as ratios. For example, the just intoned major chord in root position is 4:5:6. (When chords are expressed as ratios, the above rule about the notes being above or below a base tone doesn't usually apply).  Chords can also be written as a string of intervals, such as the major chord 1/1–5/4–3/2

In the context of just intonation, ratios are almost always used to label and identify intervals and chords. However, the use of ratios to identify intervals and chords in tempered scales is also common - in these cases, it is implied that the notes are in the //approximate// ratio indicated. For example, a common shorthand expression might be //"4:6:7:9:11 chords in [[17edo|17-EDO]]"// - which really means //"The [[chords]] in which the notes are in the approximate ratio of 4:6:7:9:11 in 17-EDO".//

Original HTML content:

<html><head><title>Ratios</title></head><body>A <strong>frequency ratio</strong> is the relationship between the frequencies of two sound waves. For example, a piano string vibrating at 110 Hz (110 times per second) and a piano string vibrating at 220 Hz are in a 2:1 ratio (since 220/110 reduces to 2/1).<br />
<br />
Ratios of frequencies may be written several ways:<br />
2/1<br />
2:1<br />
1/2<br />
1:2<br />
<br />
When the larger number is written first, this usually signifies a second note being played <em>above</em> some base tone (perhaps the starting note of a scale). When the smaller number is written first, this usually signifies the second note being played <em>below</em> that base tone.<br />
<br />
<span class="wiki_link_ext">The <a class="wiki_link_ext" href="http://en.wikipedia.org/wiki/Harmonic_series_%28music%29" rel="nofollow">harmonic series</a> can be represented as a ratio - 1:2:3:4:5:6:7:8:9:10:11:12:13:14:15:16:17... etc.</span><br />
<br />
Chords can also be expressed as ratios. For example, the just intoned major chord in root position is 4:5:6. (When chords are expressed as ratios, the above rule about the notes being above or below a base tone doesn't usually apply).  Chords can also be written as a string of intervals, such as the major chord 1/1–5/4–3/2<br />
<br />
In the context of just intonation, ratios are almost always used to label and identify intervals and chords. However, the use of ratios to identify intervals and chords in tempered scales is also common - in these cases, it is implied that the notes are in the <em>approximate</em> ratio indicated. For example, a common shorthand expression might be <em>&quot;4:6:7:9:11 chords in <a class="wiki_link" href="/17edo">17-EDO</a>&quot;</em> - which really means <em>&quot;The <a class="wiki_link" href="/chords">chords</a> in which the notes are in the approximate ratio of 4:6:7:9:11 in 17-EDO&quot;.</em></body></html>

@@ Line 1: / Line 1: @@
 <h2>IMPORTED REVISION FROM WIKISPACES</h2>
 This is an imported revision from Wikispaces. The revision metadata is included below for reference:<br>
-: This revision was by author [[User:xenwolf|xenwolf]] and made on <tt>2013-01-23 08:18:21 UTC</tt>.<br>
+: This revision was by author [[User:Omegatron|Omegatron]] and made on <tt>2014-08-13 20:29:26 UTC</tt>.<br>
-: The original revision id was <tt>400714074</tt>.<br>
+: The original revision id was <tt>518470200</tt>.<br>
-: The revision comment was: <tt>some typography, some links</tt><br>
+: The revision comment was: <tt>can't find any explanation for this notation</tt><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>
@@ Line 18: / Line 18: @@
 &lt;span class="wiki_link_ext"&gt;The [[http://en.wikipedia.org/wiki/Harmonic_series_%28music%29|harmonic series]] can be represented as a ratio - 1:2:3:4:5:6:7:8:9:10:11:12:13:14:15:16:17... etc.&lt;/span&gt;
-Chords can also be expressed as ratios. For example, the just intoned major chord in root position is 4:5:6. (When chords are expressed as ratios, the above rule about the notes being above or below a base tone doesn't usually apply).
+Chords can also be expressed as ratios. For example, the just intoned major chord in root position is 4:5:6. (When chords are expressed as ratios, the above rule about the notes being above or below a base tone doesn't usually apply).  Chords can also be written as a string of intervals, such as the major chord 1/1–5/4–3/2
 In the context of just intonation, ratios are almost always used to label and identify intervals and chords. However, the use of ratios to identify intervals and chords in tempered scales is also common - in these cases, it is implied that the notes are in the //approximate// ratio indicated. For example, a common shorthand expression might be //"4:6:7:9:11 chords in [[17edo|17-EDO]]"// - which really means //"The [[chords]] in which the notes are in the approximate ratio of 4:6:7:9:11 in 17-EDO".//</pre></div>
@@ Line 34: / Line 34: @@
 &lt;span class="wiki_link_ext"&gt;The &lt;a class="wiki_link_ext" href="http://en.wikipedia.org/wiki/Harmonic_series_%28music%29" rel="nofollow"&gt;harmonic series&lt;/a&gt; can be represented as a ratio - 1:2:3:4:5:6:7:8:9:10:11:12:13:14:15:16:17... etc.&lt;/span&gt;&lt;br /&gt;
 &lt;br /&gt;
-Chords can also be expressed as ratios. For example, the just intoned major chord in root position is 4:5:6. (When chords are expressed as ratios, the above rule about the notes being above or below a base tone doesn't usually apply).&lt;br /&gt;
+Chords can also be expressed as ratios. For example, the just intoned major chord in root position is 4:5:6. (When chords are expressed as ratios, the above rule about the notes being above or below a base tone doesn't usually apply).  Chords can also be written as a string of intervals, such as the major chord 1/1–5/4–3/2&lt;br /&gt;
 &lt;br /&gt;
 In the context of just intonation, ratios are almost always used to label and identify intervals and chords. However, the use of ratios to identify intervals and chords in tempered scales is also common - in these cases, it is implied that the notes are in the &lt;em&gt;approximate&lt;/em&gt; ratio indicated. For example, a common shorthand expression might be &lt;em&gt;&amp;quot;4:6:7:9:11 chords in &lt;a class="wiki_link" href="/17edo"&gt;17-EDO&lt;/a&gt;&amp;quot;&lt;/em&gt; - which really means &lt;em&gt;&amp;quot;The &lt;a class="wiki_link" href="/chords"&gt;chords&lt;/a&gt; in which the notes are in the approximate ratio of 4:6:7:9:11 in 17-EDO&amp;quot;.&lt;/em&gt;&lt;/body&gt;&lt;/html&gt;</pre></div>

Frequency ratio: Difference between revisions

Revision as of 20:29, 13 August 2014

IMPORTED REVISION FROM WIKISPACES

Original Wikitext content:

Original HTML content:

Navigation menu

Search