Easy Scales by Interpolating between Harmonic Series

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=Easy Scales by Interpolating between Harmonic Series= 

A very easy way to construct a scale that's instantly recognizable, even without repeated listening/priming in the absence of listening the music in 12EDO, is to interpolate between harmonic series.

I'm using the notation <<harmonic series numbers from the root>> to denote what harmonic series certain scales contain. If this seems unclear or conflicts with an existing notation, please let me know.
**Some of the most prominent scales in existence can be very quickly derived from just a few interlocked/interpolated harmonic series.**
Take, for example, the diatonic major scale in 12EDO, where notes are approximately equal to
__**C major diatonic in 12EDO <<8-9-12>> scale**__
|| C || D || E || F || G || A || B ||
|| 1/1 || 9/8 or 10/9 || 5/4 || 4/3 || 3/2 || 5/3 || 15/8 or 17/9 ||
This can be derived from the following harmonic series

**(x/9)** - 1/1, 10/9, 12/9 (4/3), 15/9 (5/3), 17/9
which is the same as the notes C D F A B and contains the **subdominant major chord F A C**
**(x/8)** - 1/1,9/8,10/8 (5/4), 12/8 (3/2), 15/8
which is the same as the notes C D E G B and contains the **tonic major chord C E G** along with the **dominant major chord G B D**
**(x/12) -** 1/1 5/4 4/3 3/2 5/3
the same as the notes C E F G A.

The **x/12 and x/9** harmonic series become particularly stressed in the **(Maqam) Rast**, also known as the **"Blues" scale**, of
__**Maqam Rast <<9-12>> scale**__
|| C || D || D#-E || F || G || A || A#-B ||
|| 1/1 || 9/8 or 10/9 || **11/9** || 4/3 || 3/2 || 5/3 or 27/16 || **11/6** ||
Here the x/9 series uses the "blue tone" of 11/9 and grows into
**(x/9)** - 1/1 10/9 **11/9** 12/9 15/9 17/9
Meanwhile the addition of the "blue tone" of 11/6 and removal of 5/4 changes the x/12 series to
**(x/12)** - 1/1 4/3 3/2 5/3 **11/6**
And the removal of the 5/4 and 15/8 shrinks the x/8 series into
**(x/8) -** 1/1 9/8 3/2

If you don't like the small/compromised x/8 series, you can modify that scale by deleting the 11/9 and adding back the 5/4 and removing the 11/9 to make the scale more balanced between the size of the different series e.g.
(x/8) - 1/1 9/8 5/4 3/2
and
(x/9) - 1/1 10/9 4/3 5/3 17/9
**But why limit yourself to/by x/8, x/9, and x/12 harmonic extensions of the root?**
----
**Part 2- Attempting to create scales from scratch given harmonic series segments from a root tone**

A common pattern in the above scales is use of and interpolation between the x/9 and x/12 harmonic series
It turns out the x/7 harmonic series has many notes in common with or close to the x/8, x/9, and x/12 harmonic series.
We can take advantage of this to construct a more advanced scale in order the create the series
**(x/7)** = 7:9:11:12:13 (AKA 1/1 9/7 11/7 12/7 13/7)
**(x/8)** = 8:9:10:12:14:15
**(x/9)** = 9:10:12:14:15
**(x/12)** = 12:15:16:18:20
Some of these ratios are near each other, but not equal, such as 9/8 in the (x/8) and 10/9 in the (x/9) series or 14/9 in the (x/9) series and 11/7 in the x/7 series.
One way to evenly distribute error is to take the harmonic/geometric median between such fractions e.g. square-root-of ((11/7)/(14/9)) * 14/9 = about 1.56.
Doing such gives us the scale
__**10 note <<7-8-9-12>> "extended color diatonic" Harmonic Segment Scale**__
|| 1/1 || 11181/10000 || 5/4 || 9/7 || 4/3 || 3/2 || 156341/100000 || 5/3 || 26/15 || 28/15 ||
||   || between 10/9 and 9/8 ||   ||   ||   ||   || between 14/9 and 11/7 ||   || between 12/7 and 7/4 || between 13/7 and 15/8 ||

In addition, adding 16/15 to the above scale can yield an additional 5 note harmonic series, making the above a **larger <<7-8-9-12-15>> scale**
**(x/15)** = 15:16:20:26:28

Feel free to add comments or find/punch loopholes in this theory, but this is what I'd consider an idea **"extended diatonic"** scale in that it stresses likely the most important harmonic series in the diatonic scale while adding an extra (x/7) into the mix, giving the scale a wider range of tonal color.
**More scales to come later...**
----
**Appendix-**
Above calculations such as the interpolation of (11/7)/(14/9) can also be expressed as commas e.g. 99/98, which can be plugged into Graham Breed's Temperament Finder on [[http://x31eq.com/temper/uv.html]] to reveal temperaments and ultimately scales likely to contain the above harmonic series segments.
. However, most of the more advanced scales on my method would require tempering out several different commas and, presumably, also countless related commas indirectly. I am afraid this would often result in huge and much more challenging to play in (think: well over 15 notes) scales needed to contain, say, the x/7,x/8,x/9,and x/12 harmonic series from the root tone with reasonable accuracy in regular temperament theory.

If any **experts on Xenharmonic math**, including related lists, can find a way to related the input of harmonic series segments to, say, MOS scales guaranteed to have them I would really appreciate it.

Original HTML content:

<html><head><title>Easy Scales by Interpolating between Harmonic Series</title></head><body><!-- ws:start:WikiTextHeadingRule:0:&lt;h1&gt; --><h1 id="toc0"><a name="Easy Scales by Interpolating between Harmonic Series"></a><!-- ws:end:WikiTextHeadingRule:0 -->Easy Scales by Interpolating between Harmonic Series</h1>
 <br />
A very easy way to construct a scale that's instantly recognizable, even without repeated listening/priming in the absence of listening the music in 12EDO, is to interpolate between harmonic series.<br />
<br />
I'm using the notation &lt;&lt;harmonic series numbers from the root&gt;&gt; to denote what harmonic series certain scales contain. If this seems unclear or conflicts with an existing notation, please let me know.<br />
<strong>Some of the most prominent scales in existence can be very quickly derived from just a few interlocked/interpolated harmonic series.</strong><br />
Take, for example, the diatonic major scale in 12EDO, where notes are approximately equal to<br />
<u><strong>C major diatonic in 12EDO &lt;&lt;8-9-12&gt;&gt; scale</strong></u><br />


<table class="wiki_table">
    <tr>
        <td>C<br />
</td>
        <td>D<br />
</td>
        <td>E<br />
</td>
        <td>F<br />
</td>
        <td>G<br />
</td>
        <td>A<br />
</td>
        <td>B<br />
</td>
    </tr>
    <tr>
        <td>1/1<br />
</td>
        <td>9/8 or 10/9<br />
</td>
        <td>5/4<br />
</td>
        <td>4/3<br />
</td>
        <td>3/2<br />
</td>
        <td>5/3<br />
</td>
        <td>15/8 or 17/9<br />
</td>
    </tr>
</table>

This can be derived from the following harmonic series<br />
<br />
<strong>(x/9)</strong> - 1/1, 10/9, 12/9 (4/3), 15/9 (5/3), 17/9<br />
which is the same as the notes C D F A B and contains the <strong>subdominant major chord F A C</strong><br />
<strong>(x/8)</strong> - 1/1,9/8,10/8 (5/4), 12/8 (3/2), 15/8<br />
which is the same as the notes C D E G B and contains the <strong>tonic major chord C E G</strong> along with the <strong>dominant major chord G B D</strong><br />
<strong>(x/12) -</strong> 1/1 5/4 4/3 3/2 5/3<br />
the same as the notes C E F G A.<br />
<br />
The <strong>x/12 and x/9</strong> harmonic series become particularly stressed in the <strong>(Maqam) Rast</strong>, also known as the <strong>&quot;Blues&quot; scale</strong>, of<br />
<u><strong>Maqam Rast &lt;&lt;9-12&gt;&gt; scale</strong></u><br />


<table class="wiki_table">
    <tr>
        <td>C<br />
</td>
        <td>D<br />
</td>
        <td>D#-E<br />
</td>
        <td>F<br />
</td>
        <td>G<br />
</td>
        <td>A<br />
</td>
        <td>A#-B<br />
</td>
    </tr>
    <tr>
        <td>1/1<br />
</td>
        <td>9/8 or 10/9<br />
</td>
        <td><strong>11/9</strong><br />
</td>
        <td>4/3<br />
</td>
        <td>3/2<br />
</td>
        <td>5/3 or 27/16<br />
</td>
        <td><strong>11/6</strong><br />
</td>
    </tr>
</table>

Here the x/9 series uses the &quot;blue tone&quot; of 11/9 and grows into<br />
<strong>(x/9)</strong> - 1/1 10/9 <strong>11/9</strong> 12/9 15/9 17/9<br />
Meanwhile the addition of the &quot;blue tone&quot; of 11/6 and removal of 5/4 changes the x/12 series to<br />
<strong>(x/12)</strong> - 1/1 4/3 3/2 5/3 <strong>11/6</strong><br />
And the removal of the 5/4 and 15/8 shrinks the x/8 series into<br />
<strong>(x/8) -</strong> 1/1 9/8 3/2<br />
<br />
If you don't like the small/compromised x/8 series, you can modify that scale by deleting the 11/9 and adding back the 5/4 and removing the 11/9 to make the scale more balanced between the size of the different series e.g.<br />
(x/8) - 1/1 9/8 5/4 3/2<br />
and<br />
(x/9) - 1/1 10/9 4/3 5/3 17/9<br />
<strong>But why limit yourself to/by x/8, x/9, and x/12 harmonic extensions of the root?</strong><br />
<hr />
<strong>Part 2- Attempting to create scales from scratch given harmonic series segments from a root tone</strong><br />
<br />
A common pattern in the above scales is use of and interpolation between the x/9 and x/12 harmonic series<br />
It turns out the x/7 harmonic series has many notes in common with or close to the x/8, x/9, and x/12 harmonic series.<br />
We can take advantage of this to construct a more advanced scale in order the create the series<br />
<strong>(x/7)</strong> = 7:9:11:12:13 (AKA 1/1 9/7 11/7 12/7 13/7)<br />
<strong>(x/8)</strong> = 8:9:10:12:14:15<br />
<strong>(x/9)</strong> = 9:10:12:14:15<br />
<strong>(x/12)</strong> = 12:15:16:18:20<br />
Some of these ratios are near each other, but not equal, such as 9/8 in the (x/8) and 10/9 in the (x/9) series or 14/9 in the (x/9) series and 11/7 in the x/7 series.<br />
One way to evenly distribute error is to take the harmonic/geometric median between such fractions e.g. square-root-of ((11/7)/(14/9)) * 14/9 = about 1.56.<br />
Doing such gives us the scale<br />
<u><strong>10 note &lt;&lt;7-8-9-12&gt;&gt; &quot;extended color diatonic&quot; Harmonic Segment Scale</strong></u><br />


<table class="wiki_table">
    <tr>
        <td>1/1<br />
</td>
        <td>11181/10000<br />
</td>
        <td>5/4<br />
</td>
        <td>9/7<br />
</td>
        <td>4/3<br />
</td>
        <td>3/2<br />
</td>
        <td>156341/100000<br />
</td>
        <td>5/3<br />
</td>
        <td>26/15<br />
</td>
        <td>28/15<br />
</td>
    </tr>
    <tr>
        <td><br />
</td>
        <td>between 10/9 and 9/8<br />
</td>
        <td><br />
</td>
        <td><br />
</td>
        <td><br />
</td>
        <td><br />
</td>
        <td>between 14/9 and 11/7<br />
</td>
        <td><br />
</td>
        <td>between 12/7 and 7/4<br />
</td>
        <td>between 13/7 and 15/8<br />
</td>
    </tr>
</table>

<br />
In addition, adding 16/15 to the above scale can yield an additional 5 note harmonic series, making the above a <strong>larger &lt;&lt;7-8-9-12-15&gt;&gt; scale</strong><br />
<strong>(x/15)</strong> = 15:16:20:26:28<br />
<br />
Feel free to add comments or find/punch loopholes in this theory, but this is what I'd consider an idea <strong>&quot;extended diatonic&quot;</strong> scale in that it stresses likely the most important harmonic series in the diatonic scale while adding an extra (x/7) into the mix, giving the scale a wider range of tonal color.<br />
<strong>More scales to come later...</strong><br />
<hr />
<strong>Appendix-</strong><br />
Above calculations such as the interpolation of (11/7)/(14/9) can also be expressed as commas e.g. 99/98, which can be plugged into Graham Breed's Temperament Finder on <a class="wiki_link_ext" href="http://x31eq.com/temper/uv.html" rel="nofollow">http://x31eq.com/temper/uv.html</a> to reveal temperaments and ultimately scales likely to contain the above harmonic series segments.<br />
. However, most of the more advanced scales on my method would require tempering out several different commas and, presumably, also countless related commas indirectly. I am afraid this would often result in huge and much more challenging to play in (think: well over 15 notes) scales needed to contain, say, the x/7,x/8,x/9,and x/12 harmonic series from the root tone with reasonable accuracy in regular temperament theory.<br />
<br />
If any <strong>experts on Xenharmonic math</strong>, including related lists, can find a way to related the input of harmonic series segments to, say, MOS scales guaranteed to have them I would really appreciate it.</body></html>