Pinetone

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Revision as of 18:48, 1 March 2022 by Lhearne (talk | contribs) (The porcutone octatonic: work in progress)
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Are you interested in microtonal music with wild and wacky harmonies but want some familiarity to guide you? Heard about this Porcupine thing but not sure how to get 12 notes of it? Wish you had something like Porcupine but more accurate or with more interesting scales? Introducing The Porcutone System. The scales you know and love, with a new-age quirky spin. The perfect mix of consonant and dissonant harmonies, familiar and newfangled. Try it on your keyboard straight away (if you can return your keyboard using scale files, grab this one! Copy the text into notepad and save as a .scl file).

The porcutone system combines Porcupine – arguably the best way to add the 11th harmonic to major and minor harmonies in a seven-note scale – with with Meantone – the system underpinning most common practice music from the last several hundred years, so all the same scales (diatonic, harmonic minor, pentatonic, chromatic, etc.) are still available, just with a new Porcupine spin, and the 11th harmonic!

While there aren't as many consonant major and minor triads as we are used to, they are more consonant in Porcutone.

As opposed to in 12edo, each key is distinctly different in porcutone, both a blessing and a curse.

Additionally available in porcutone are a set of octatonic modes with their own Porcupine functional harmony, that combine Porcupine[8] with the oneirotonic modes that are gaining popularity at the moment.

If you have a Lumatone, you can use the standard Bosanquet mapping for 12edo. The white keys are the porcutone diatonic, a cross between the meantone diatonic scale and Porcupine[7], and then black keys give the porcutone pentatonic, which approximates the just intonation pentatonic scale 9/8 5/4 3/2 5/3 2/1. I've chosen to colour the G♯/Ab key pink, and the other chromatic keys blue, because I'm a proud trans woman and a big nerd. You can use any colours, but I find it helps to colour the G♯/A♭ key a different colour since that's the one chromatic key used along with the diatonic keys to make the porcutone octatonic.

How it works - Porcutone diatonic

The diatonic scale has a step signature of 5L 2s, meaning it has 5 large steps and 2 small step arranged in the step pattern LsLLLsL (represent in mode 0, Dorian mode). In Meantone[7], the large step represents both 9/8 and 10/9, the major and minor tones (tempering out the 81/80 that separates them) hence the name "Meantone". The small step represents 16/15 and 27/25 (which differ again by 81/80). We write this as 5L 2s = (9/8~10/9, 16/15~27/25). Porcupine[7] instead has step step signature and step mapping 1L 6s = (~9/8, 10/9~27/25), hence the difference between 10/9 and 27/25, 250/243, is tempered out. In mode 0 it has step pattern sssLsss. 81/80 is called the Meantone comma, and 250/243 is called the Porcupine comma.

We are familiar with the Zarlino/Ptolemy just major scale: 9/8 5/4 4/3 3/2 5/3 15/8 2/1. This scale has 3 large steps of 9/8, 2 medium steps of 10/9, and 2 small steps of 16/15, with step pattern LMsLMLs. If we temper out the difference between L and M, we get LLsLLLs, the mode 2 of Meantone[7], the familiar Ionian/major mode.

Consider instead the just scale: 10/9 6/5 4/3 3/2 5/3 9/5 2/1, a just Dorian scale. This scale has 1 large step of 9/8, 4 medium steps of 10/9, and 2 small steps of 27/25, with step pattern MsMLMsM (mode 0). It can be represented with step signature and step mapping 1L 4M 2s = (9/8, 10/9, 27/25). This is our just porcutone diatonic.If we temper out the difference between L and M, we get LsLLLsL, Meantone[7] mode 0: Dorian; if we temper out instead the difference between 10/9 and 27/25, we get sssLsss, Porcupine[7] mode 0, which is referred to as symmetric minor. In this way, the just porcutone diatonic represents both Porcupine[7] and Meantone[7].

To name this mode of the porcutone diatonic, we simply add the mode names together, prefixing the Porcupine[7] functional mode name (which I am introducing here) with the meantone diatonic mode name, so mode 0 of the porcutone diatonic is called Dorian symmetric minor. We continue this process with the other 6 modes:

Modes of the just porcutone diatonic
Mode number Mode in JI Step pattern Meantone[7] Diatonic mode Porcupine[7] Porcupine[7] mode Porcutone diatonic mode
3 10/9 5/4 25/18 3/2 5/3 50/27 2/1 MLMsMMs LLLsLLs Lydian sLsssss Dark major Lydian dark major
2 9/8 5/4 27/20 3/2 5/3 9/5 2/1 LMsMMsM LLsLLsL Mixolydian Lssssss Bright major Mixolydian bright minor
1 10/9 100/81 4/3 40/27 5/3 50/27 2/1 MMsMLMs LLsLLLs Ionian ssssLss Bright diminished Ionian bright diminished
0 10/9 6/5 4/3 3/2 5/3 9/5 2/1 MsMLMsM LsLLLsL Dorian sssLsss Symmetric minor Dorian symmetric minor
-1 27/25 6/5 27/20 3/2 81/50 9/5 2/1 sMLMsMM sLLLsLL Phrygian ssLssss Bright minor Phrygian bright minor
-2 10/9 6/5 4/3 40/27 8/5 16/9 2/1 MsMMsML LsLLsLL Aeolian ssssssL Magical seventh Aeolian magical seventh
-3 27/25 6/5 4/3 36/25 8/5 9/5 2/1 sMMsMLM sLLsLLL Locrian sssssLs Dark diminished Locrian dark diminished

Like Meantone[7] and Porcupine[7], and unlike the Ptolemy/Zarlino just major scale, the porcutone diatonic scale is mirror symmetric, meaning that the mirror inverse of any mode of the scale is also a mode of the scale, i.e., if we trace the steps of the mode from the top instead of from the bottom. This is reflected with the mode numbers. The mirror inverse of mode 3, the brightest mode, is mode -3, the darkest mode, and mode 0 is itself a symmetric mode, hence 'symmetric' in the mode name. We may already know this - that the Dorian mode of the familiar diatonic scale is symmetric, and the mirror inverse of the Lydian mode is the Locrian mode.

Something to note - the Meantone diatonic scale is generated by the perfect fifth, 3/2, which means that it can be formed by stacking perfect fifths on top of each other, i.e., F-C-G-D-A-E, and all the notes are connected by perfect fifths. Porcupine[7], on the other hand, is generated by 10/9, so all notes are connected by a chain of 10/9s, i.e., A-B-C-D-E-F-G, where the large step of 9/8 then separates G from A. The Zarlino/Ptolemy just major scale 9/8 5/4 4/3 3/2 5/3 15/8 2/1 can be built of two parallel chains of 3/2, i.e., 4/3-2/1-3/2-9/8, 5/3-5/4-15/8. Accordingly it is a generator-offset scale. If the scale is on C, then D-A is not a 3/2 perfect fifth, but a wolf fifth of 40/27. The porcutone diatonic is not a generator offset scale. Setting the scale to the naturals, D E F G A B C D, 3/2 perfect fifths are available above D, E, F, and C, so there are 1 fewer 3/2 perfect fifths in the porcutone diatonic scale than in the Zarlino/Ptolemy just major scale, and two fewer than in the typical diatonic scale. Porcupine[7] also has 3/2 fifths only above D, E, F, and C. It is because 3/2 perfect fifths are available above D, E, F, and C in both Meantone[7] and Porcupine[7] that they are available above D, E, F, and C in the Porcutone diatonic.

The minor tone small step of Porcupine[7] can also represent the neutral seconds 11/10 and 12/11, since 10/9*11/10*12/11 = 4/3, and 4/3 is subtended by 3 small steps of Porcupine[7], tempering out both 100/99 and 121/120. 11/8 is easily reached in Porcupine[7] as a major 4th, subtended by 2 small steps and 1 large step. The small step of Porcupine[7] represents all of 10/9, 11/10, 12/11 and 27/25, in order of largest to smallest. In the porcutone diatonic, the small step is 27/25 and the medium step is 10/9. We can access our 11-limit harmonies in porcutone by tempering out 100/99, which separates 10/9 from 11/10, as well as 27/25 from 12/11. This leads to step signature and step mapping 1L 4M 2s = (9/8~25/22, 10/9~11/10, 27/25~12/11). Since 100/99 is called the Ptolemisma, we can call the resulting scale the ptolemismic porcutone diatonic.

The modes of the ptolemismic porcutone diatonic are shown below in their simplest JI pre-image (the simplest JI ratios each interval above the tonic represents), and in cents, in an optimized tuning called TE tuning.

Modes of the ptolemismic porcutone diatonic
Porcutone diatonic mode Step pattern Mode as simplest JI pre-image Mode in cents
Lydian dark major mLmsmms ~ 10/9 5/4 11/8 3/2 5/3 11/6 2/1 174.055 383.834 557.888 704.524 878.579 1052.633 1199.269
Mixolydian bright minor Lmsmmsm ~ 9/8 5/4 15/11 3/2 5/3 9/5 2/1 209.779 383.834 530.469 704.524 878.579 1025.214 1199.269
Ionian bright diminished mmsmLms ~ 10/9 11/9 4/3 22/15 5/3 11/6 2/1 174.055 348.110 494.745 668.800 878.579 1052.633 1199.269
Dorian symmetric minor msmLmsm ~ 10/9 6/5 4/3 3/2 5/3 9/5 2/1 174.055 320.690 494.745 704.524 878.579 1025.214 1199.269
Phrygian bright minor smLmsmm ~ 12/11 6/5 15/11 3/2 18/11 9/5 2/1 146.635 320.690 530.469 704.524 851.159 1025.214 1199.269
Aeolian magical seventh msmmsmL ~ 10/9 6/5 4/3 22/15 8/5 16/9 2/1 174.055 320.690 494.745 668.800 815.435 989.490 1199.269
Locrian dark diminished smmsmLm ~ 12/11 6/5 4/3 16/11 8/5 9/5 2/1 146.635 320.690 494.745 641.380 815.435 1025.214 1199.269

We see 11/8 as the 4th in Lydian dark major. In Meantone[7] this is an augmented fourth. The meantone extension representing 11/8 with an augmented fourth is called Meanenneadecal, referencing the fact that it is most at home in 19edo. Tuning the scale to 19edo (or 12edo or 31edo) will collapse it into a Meanenneadecal[7] diatonic scale. Similarly, tuning the scale to 15edo, 22edo, or 29edo will collapse it to Porcupine[7] scale. 27edo, 34edo, and 41edo are good tunings for the porcutone diatonic if tuning to an edo is desired.

27edo: 1L 4m 2s = (5, 4, 3) = (222.2222c, 177.7778c, 133.3333c)

34edo: 1L 4m 2s = (6, 5, 4) = (211.7647c, 176.4706c, 141.1765c)

41edo: 1L 4m 2s = (7, 6, 5) = (204.8780c, 175.6098c, 146.3415c)

We might also relax the tuning of the octave to optimize the tuning of the scale as a whole, leading to the following TE tunings of the scales

27edo with 1195.1825c octave: 1L 4m 2s = (5, 4, 3) = (221.3301c, 177.0641c, 132.7981c)

34edo with 1198.2070c octave: 1L 4m 2s = (6, 5, 4) = (211.4483c, 176.2069c, 140.9655c)

41edo with 1200.2039c octave: 1L 4m 2s = (7, 6, 5) = (204.9129c, 175.6396c, 146.3663c)

The table below show the sizes, interval names, ratios approximated, tuning, and occurence of all intervals of the ptolemismic porcutone diatonic scale within an octave, tuned to TE tuning.

Intervals of the porcutone diatonic
Interval class sizes Meantone[7] names Porcupine[7] names Porcutone diatonic names JI ratios approximated size in cents (TE) Occurence
1-step s

m

L

minor 2nd

major 2nd

major 2nd

minor 2nd

minor 2nd

major 2nd

small 2nd

medium 2nd

large 2nd

27/25, 12/11

10/9, 11/10

9/8, 25/22

146.635

174.055

209.779

2

4

1

2-step m + s

m + m

L + m

minor 3rd

major 3rd

major 3rd

minor 3rd

minor 3rd

major 3rd

small 3rd

medium 3rd

large 3rd

6/5, 40/33

100/81, 11/9

5/4, 33/20

320.690

348.110

383.834

4

1

2

3-step 2m + s

L + m + s

L + 2m

perfect 4th

perfect 4th

augmented 4th

minor 4th

major 4th

major 4th

small 4th

medium 4th

large 4th

4/3, 33/25

27/20, 15/11

25/18, 11/8

494.745

530.469

557.888

4

2

1

4-step 2m + 2s

3m + s

L + 2m + s

diminished 5th

perfect 5th

perfect 5th

minor 5th

minor 5th

major 5th

small 5th

medium 5th

large 5th

36/25, 16/11

40/27, 22/15

3/2, 50/33

641.380

668.800

704.524

1

2

4

5-step 3m + 2s

L + 2m + 2s

L + 3m + s

minor 6th

minor 6th

major 6th

minor 6th

major 6th

major 6th

small 6th

medium 6th

large 6th

8/5, 40/33

81/50, 18/11

5/3, 33/20

815.435

851.159

878.579

2

1

4

6-step 4m + 2s

L + 3m + 2s

L + 4m + s

minor 7th

minor 7th

major 7th

minor 7th

major 7th

major 7th

small 7th

medium 7th

large 7th

16/9, 44/25

9/5, 20/11

11/6, 50/27

989.490

1025.241

1052.633

1

4

2

The porcutone pentatonic and the porcutone chromatic

Using the familiar Bosanquet 12-note keyboard mapping (the preset for 12edo), we set the porcutone diatonic scale to the white keys, starting on D. We than add, on F♯/G♭, the porcutone pernatonic as a set of 5 chromatic keys. There are two options for the chromatic keys, either all sharps or all flats. All sharps makes the porcutone harmonic minor available, and all flats makes the porcutone harmonic major available. These scales will be discussed below. In either case, in the just tuning, the chromatic keys give the scale 9/8 5/4 3/2 5/3 2/1, starting from F♯/G♭, tuned to 100/81 (F♯) or 162/125 (G♭) from D. This scale has step pattern msLsL, with step signature and step mapping 2L 1m 2s = (6/5, 9/8, 10/9). We are familiar with this scale as the just pentatonic. If we temper m and s together, we get Meantone[5]: ssLsL. If we temper m and L together instead we get a scale called Father[5], tempering out the diatonic semitone 16/15. This mode of Father[5] has step pattern LsLsL. Keep the connection to Father[5] in the back of your minds for now, we'll come back to it.

Adding these notes leads to the just porcutone chromatic, a 12-note mirror-symmetric scale with step signature and step mapping of 7L 1m 4s = (27/25, 25/24, 250/243) = (133.2376c, 70.6724c, 49.1661c), i.e., 7 large steps of what was the small step of the just porcutone diatonic, 1 medium step of the chromatic semitone 25/24, the distance between 6/5 and 5/4, and 4 small steps of 250/243, the porcupine comma, that separates 10/9 from 27/25. For the all sharps scale, we set mode -3 on D (for all flats we set mode 3 on D): 250/243 10/9 6/5 100/81 4/3 25/18 3/2 125/81 5/3 9/5 50/27 2/1, with step pattern sLLsLmLsLLsL.

The now familiar Meantone comma of 81/80 separates the medium step (25/24) from the small step (250/243), so our porcutone chromatic is a detempering of Meantone[12], the meantone chromatic scale, just like how the porcutone diatonic is a detempering of Meantone[7], the meantone diatonic scale.

The ptolemismic porcutone chromatic has a step signature, mapping, and TE tuning of 7L 1m 4s = (27/25~12/11, 25/24~33/32, 250/243~55/54~121/120) = (146.6352c, 63.1434c, 27.4197c).

Mode -3 approximates the JI ratios: 55/54 10/9 6/5 11/9 4/3 11/8 3/2 55/36 5/3 9/5 11/6 2/1.

The TE tuning in cents is: 27.420 174.055 320.690 348.110 494.745 557.888 704.524 731.943 878.579 1025.214 1052.633 1199.269

Mode 3, the mirror inverse of mode -3, approximates the JI ratios: 12/11 10/9 6/5 72/55 4/3 16/11 3/2 18/11 5/3 9/5 108/55 2/1.

The TE tuning in cents is: 146.636 174.055 320.690 467.326 494.745 641.381 704.524 851.159 878.579 1025.214 1171.849 1199.269

The ptolemismic porcutone chromatic scale is distinctly xenharmonic, and yet is related to the familiar chromatic scale.

As with the porcutone diatonic, tuning the porcutone chromatic to 19edo or 31edo collapses it to the Meantone[12] (Meanenneadecal[12]) chromatic scale. Tuning it to 15edo, 22edo, or 29edo collapses it to Porcupine[8]. Step patterns, mappings and sizes for tunings to 27edo, 34edo, and 41edo are as follows:

27edo: 7L 1m 4s = (3, 2, 1) = (133.3333c, 88.8889c, 44.4444c)

34edo: 7L 1m 4s = (4, 2, 1) = (141.1765c, 70.5882c, 35.2941c)

41edo: 7L 1m 4s = (5, 2, 1) = (146.3415c, 58.5366c, 29.2683c)

And allowing octave stretch, the tuning may be optimized via TE tuning to:

27edo with 1195.1825c octave: 7L 1m 4s = (3, 2, 1) = (132.7981c, 88.5320c, 44.2660c)

34edo with 1198.2070c octave: 7L 1m 4s = (4, 2, 1) = (140.9655c, 70.4828c, 35.2414c)

41edo with 1200.2039c octave: 7L 1m 4s = (5, 2, 1) = (146.3663c, 58.5465c, 29.2733c)

The porcutone octatonic

The porcupine comma is the small step of the scale, so tempering the porcutone chromatic scale to porcupine leads from 7L 1m 4s = (27/25, 25/24, 250/243) to 7L 1s = (10/9~27/25, 25/24~81/80), which is Porcupine[8]! The Porcupine[7] scale has its large step between G and A, so the eighth note of Porcupine[8] is either G♯ or A♭, adding another small step of Porcupine[7] below A (for G♯) or above G (A♭). Mode -3 or mode 3 of the porcutone chromatic scale, respectively, are set to D so that this is preserved in The Porcutone System. This leads to the porcutone octatonic scales: D E F G G♯/A♭ A B C. In Just intonation: 10/9 6/5 4/3 25/18 3/2 5/3 9/5 2/1 with G♯, or 10/9 6/5 4/3 36/25 3/2 5/3 9/5 2/1 with A♭. This scale has 4 large steps of 10/9, 3 medium steps of 27/25, and 1 small step of 25/24. It is not mirror-symmetric, or equivalentely, it is chiral so it cannot be uniquely defined with a step signature like Meantone[7], Porcupine[7], Porcupine[8], Meantone[12], and the porcutone diatonic (the Zarlio/Ptolemy just major scale is also not mirror symmetric). Scales that can be uniquely defined by a step signature are called step-nested scales. More on that later. The mirror inverse of any mode of the porcutone octatonic with G♯ is a mode of the porcutone octatonic with A♭. The porcutone octatonic with G♯ is called the left handed porcupine octatonic, and the porcutone octatonic with A♭ is called the right handed porcupine octatonic (see chirality).

If we temper out the difference between the large and medium steps, we reduce the scale to Porcupine[8]. As we discussed above, Porcupine is generated by the interval 10/9. The table below introduces a set of functional mode names for Porcupine[8]. Along with the step pattern and mode number, the modes' UDP is show in the table. The UDP show the number of generators in the direction the brighten the intervals of scale, followed the number of generators in the direction that darkens it, (followed by the number of periods per octave, if it is not one. In this case the scale repeats at the octave, so P = 1, and is not shown). Instead of building chords by stacking thirds (2-step intervals), in octatonic scales we can build major and minor triads by stacking 3-step intervals! Instead of diminished, we get modes with two large fourths making a quartal chord: Accordingly we call these modes 'quartal'. When we stack 3-step intervals of 8-note scales out minor triads come in first inversion, and our major triads come in second inversion, as the 3-step intervals of octatonic scales include 5/4 and 4/3. Hence the brightest modes are quartal, and the darkest are minor.

Porcupine[8] functional mode names
Mode number Step pattern UDP Mode name
4 LLLLLLLs 7|0 Bright quartal
3 LLLLLLsL 6|1 Dark quartal
2 LLLLLsLL 5|2 Bright major
1 LLLLsLLL 4|3 Middle major
-1 LLLsLLLL 3|4 Dark major
-2 LLsLLLLL 2|5 Bright minor
-3 LsLLLLLL 1|6 Middle minor
-4 sLLLLLLL 0|7 Dark minor


We get Father[8], instead, if we temper out the difference (16/15) between the large step and the small step. Recall that the porcupine pentatonic reduces to Father[5], a subset of Father[8]. Father scales are generated by an interval representing both 5/4 and 4/3 (the 3-step interval of 8-note scales). The modes of Father[8] have names in use already, as an oneirotonic. These are shown in the table below with the mode number, step patter, and UDP.

Father[8] oneirotonic mode names
Mode number Step pattern UDP Mode name
4 LLsLLsLs 7|0 Dylathian (də-LA(H)TH-iən)
3 LLsLsLLs 6|1 Illarnekian (ill-ar-NEK-iən)
2 LsLLsLLs 5|2 Celephaïsian (kel-ə-FAY-zhən)
1 LsLLsLsL 4|3 Ultharian (ul-THA(I)R-iən)
-1 LsLsLLsL 3|4 Mnarian (mə-NA(I)R-iən)
-2 sLLsLLsL 2|5 Kadathian (kə-DA(H)TH-iən)
-3 sLLsLsLL 1|6 Hlanithian (lə-NITH-iən)
-4 sLsLLsLL 0|7 Sarnathian (sar-NA(H)TH-iən), can be shortened to "Sarn"

For our modes of the left handed and right handed porcupine octatonic scales we prefix the functional mode names for Porcupine[8], with the oneirotonic mode names associated with Father[8]. Like in the tables of modes of the porcutone diatonic, the modes are listed in order of brightest, with the brightest mode at the top, and the darkest mode at the bottom.

Left handed just Porcutone octatonic
mode in JI step pattern Porcupine[8]

step pattern and UDP

Porcupine[8]

mode

Father[8]

step pattern and UDP

Father[8]

mode

Porcutone octatonic

mode

10/9 6/5 4/3 40/27 8/5 16/9 50/27 2/1 LMLLMLsM LLLLLLsL 6|1 Dark quartal LsLLsLLs 5|2 Celephaïsian Celephaïsian dark quartal
27/25 6/5 162/125 36/25 8/5 216/125 48/25 2/1 MLMLLMLs LLLLLLLs 7|0 Bright quartal sLsLLsLL 0|7 Sarnathian Sarnathian bright quartal
10/9 100/81 4/3 40/27 125/81 5/3 50/27 2/1 LLMLsMLM LLLLsLLL 4|3 Middle major LLsLLsLs 7|0 Dylathian Dylathian middle major
27/25 6/5 4/3 36/25 8/5 5/3 9/5 2/1 MLLMLsML LLLLLsLL 5|2 Bright major sLLsLLsL 2|5 Kadathian Kadathian bright major
10/9 6/5 4/3 25/18 3/2 5/3 9/5 2/1 LMLsMLML LLLsLLLL 3|4 Dark major LsLLsLsL 4|3 Ultharian Ultharian dark major
10/9 125/108 5/4 25/18 3/2 5/3 50/27 2/1 LsMLMLLM LsLLLLLL 1|6 Middle minor LLsLsLLs 6|1 Illarnekian Illarnekian middle minor
27/25 6/5 5/4 27/20 3/2 81/50 9/5 2/1 MLsMLMLL LLsLLLLL 2|5 Bright minor sLLsLsLL 1|6 Hlanithian Hlanithian bright minor
25/24 9/8 5/4 27/20 3/2 5/3 9/5 2/1 sMLMLLML sLLLLLLL 0|7 Dark minor LsLsLLsL 3|4 Mnarian Mnarian dark minor
Right handed just Porcutone octatonic
mode in JI step pattern Porcupine[8]

step pattern and UDP

Porcupine[8]

mode

Father[8]

step pattern and UDP

Father[8]

mode

Porcutone octatonic

mode

10/9 6/5 4/3 40/27 8/5 16/9 50/27 2/1 LMLLMLMs LLLLLLLs 7|0 Bright quartal LsLLsLsL 4|3 Ultharian Ultharian bright quartal
27/25 6/5 162/125 36/25 8/5 216/125 48/25 2/1 LLMLMsLM LLLLLsLL 5|2 Bright major LLsLsLLs 6|1 Illarnekian Illarnekian bright major
10/9 100/81 4/3 40/27 125/81 5/3 50/27 2/1 MLLMLMsL LLLLLLsL 6|1 Dark quartal sLLsLsLL 1|6 Hlanithian Hlanithian dark quartal
27/25 6/5 4/3 36/25 8/5 5/3 9/5 2/1 LMLMsLML LLLLsLLL 4|3 Middle major LsLsLLsL 3|4 Mnarian Mnarian middle major
10/9 6/5 4/3 25/18 3/2 5/3 9/5 2/1 LMsLMLLM LLsLLLLL 2|5 Bright minor LsLLsLLs 5|2 Celephaïsian Celephaïsian bright minor
10/9 125/108 5/4 25/18 3/2 5/3 50/27 2/1 MLMsLMLL LLLsLLLL 3|4 Middle minor sLsLLsLL 0|7 Sarnathian Sarnathian dark major
27/25 6/5 5/4 27/20 3/2 81/50 9/5 2/1 sLMLLMLM sLLLLLLL 0|7 Bright minor LLsLLsLs 7|0 Dylathian Dylathian dark minor
25/24 9/8 5/4 27/20 3/2 5/3 9/5 2/1 MsLMLLML LsLLLLLL 1|6 Dark minor sLLsLLsL 2|5 Kadathian Kadathian middle minor

Summary for xen-math nerds

The Porcutone system is built via step nesting from the 5-limit minor seventh tetrad: 6/5 3/2 9/5 2/1. It's a 12-note rank-3 Meantone[12] x Ripple[12] Fokker block, a step-nested scale that also tempers to Porcupine[8], comprising a diatonic Meantone[7]-Porcupine[7]-Dicot[7] wakalix / 3-SNS on the white keys, and a pentatonic Meantone[5]-Father[5]-Bug[5] wakalix on the 'black' keys.

For the accompanying mapping for the Lumatone keyboard the G# / Ab key is coloured pink (and the remaining chromatic keys blue), and along with the white keys makes a Porcupine[8] / Father[8] Fokker block (any colours could be chosen instead of white, pink, and blue).

The Porcutone diatonic is a wakalix (pairwise well-formed scale) and a step-nested scale: A detempering of Meantone[7] and Porcupine[7], (and also of Dicot[7]), a Fokker block with unison vectors of 81/80 and 250/243 (and 25/24) has 1 large step of 9/8 (L x L), 3 medium steps of 10/9 (L x s), and 3 small steps of 27/25 (s x s).

Porcutone chromatic and Porcutone octatonic

If we put the small step into every medium and large step, we get the Porcutone chromatic, which is a detempering of Meantone[12]. (It’s also a detempering of a MODMOS of Diminished[12], and of Ripple[12]).

The just Porcutone chromatic has 7 large steps of 27/25, 1 medium step of 25/24, and 4 small steps of the porcupine comma, 250/243, hence it also tempers to Porcupine[8].

Tempering out 100/99, the Ptolemismic Porcutone chromatic has 7 large steps of 12/11~27/25, 1 medium step of 25/24~33/32, and 7 small steps of 250/243~55/54 (Here for TE steps)

Porcupine[7] has generator chain G-F-E-D-C-B-A. Porcupine[8] adds one note to the generator chain. Using Porcupine[7] note names, that’s either Ab or G#.

If we use a Bosanquet mapping on a keyboard using, we can map the porcutone diatonic to 7 white keys and the porcutone chromatic to 7 white keys and 5 chromatic keys. We colour the chromatic keys blue, apart from G#, which we colour pink, so that the white and pink keys make a porcutone octatonic scale, a detempered Porcupine[8]. This gives us a Meantone gamut of F-A#, and we also get a porcutone pentatonic on the blue and pink keys – F#-G#-A#-C#-D#.

Starting from D, the white keys gives us a Dorian symmetric minor scale, the white and pink keys gives us the just porcutone octatonic: 10/9 6/5 4/3 11/8 3/2 5/3 9/5 2/1, and the white, pink, and blue keys gives the just porcutone chromatic mode -3:

250/243 10/9 6/5 100/81 4/3 25/18 3/2 125/81 5/3 9/5 50/27 2/1 as D D# E F F# G G# A A# B C C#: Meantone[7] mode 3|8.

Tempering out 100/99, our Ptolemismic porcutone octatonic and chromatic are

~ 10/9 6/5 4/3 11/8 3/2 5/3 9/5 2/1 as D E F G G# A B C D

~ 55/54 10/9 6/5 11/9 4/3 11/8 3/2 55/36 5/3 9/5 11/6 2/1 as D D# E F F# G G# A A# B C C# D.

Or in cents: 174.055 320.69 494.745 557.888 704.524 878.579 1025.214 1199.269

27.42 174.055 320.69 348.11 494.745 557.888 704.524 731.943 878.579 1025.214 1052.633 1199.269.

Just porcutone octatonic: 4 large steps of 10/9, 3 medium of 27/25 and 1 small step of 25/24. It also tempers to a MODMOS of Diminished[8], and to Father[8].

Let’s introduce functional mode names for Porcupine[8]:

  • Mode 4: LLLLLLLs – Bright quartal
  • Mode 3: LLLLLLsL – Dark quartal
  • Mode 2: LLLLLsLL – Bright major
  • Mode 1: LLLLsLLL – middle major
  • Mode -1: LLLsLLLL – dark major
  • Mode -2: LLsLLLLL – bright minor
  • Mode -3: LsLLLLLL – middle minor
  • Mode -4: sLLLLLLL – dark minor

For our porcutone octatonic mode names, we can prefix these with the oneirotonic mode names, since it tempers to Father[8].

Using a G# instead of an Ab, we get the following modes for porcutone octatonic a:

  • Mode 4a: LMLLMLsM -> Porcupine[8]: LLLLLLsL 6|1, Father[8]: LsLLsLLs 4|3 -> Celephaïsian dark quartal
  • Mode 3a: MLMLLMLs -> Porcupine[8]: LLLLLLLs 7|0, Father[8]: sLsLLsLL 0|7 -> Sarnathian bright quartal
  • Mode 2a: LLMLsMLM -> Porcupine[8]: LLLLsLLL 4|3, Father[8]: LLsLLsLs 7|0 -> Dylathian middle major
  • Mode 1a: MLLMLsML -> Porcupine[8]: LLLLLsLL 5|2, Father[8]: sLLsLLsL 2|5 -> Kadathian bright major
  • Mode -1a: LMLsMLML -> Porcupine[8]: LLLsLLLL 3|4, Father[8]: LsLLsLsL 5|2 -> Ultharian dark major
  • Mode -2a: LsMLMLLM -> Porcupine[8]: LsLLLLLL 1|6, Father[8]: LLsLsLLs 6|1 -> Illarnekian middle minor
  • Mode -3a: MLsMLMLL -> Porcupine[8]: LLsLLLLL 2|5, Father[8]: sLLsLsLL 1|6 -> Hlanithian bright minor
  • Mode -4a: sMLMLLML -> Porcupine[8]: sLLLLLLL 0|7, Father[8]: LsLsLLsL 3|4 -> Mnarian dark minor

We could have chosen to include Ab instead of G# in the porcutone octatonic, which would result in the inverse of everything above, i.e., a chromatic gamut of Gb-B and inverses of the 8 porcutone octatonic modes resulting a different set of modes.

Porcutone octatonic b:

~ 10/9 6/5 4/3 16/11 3/2 5/3 9/5 2/1 as D E F G Ab A B C D

~ 12/11 10/9 6/5 72/55 4/3 16/11 3/2 18/11 5/3 9/5 108/55 2/1 as D Eb E F Gb G Ab A Bb B C Db D.

Porcutone octatonic b: 174.055 320.69 494.745 641.38 704.524 878.579 1025.214 1199.269

Porcutone Chromatic (Gb-B): 146.635 174.055 320.69 467.325 494.745 641.38 704.524 851.159 878.579 1025.214 1171.849 1199.269

Porcutone harmonic minor and harmonic major

Additionally, we have another set of Porcupine[7] modes contained in the Porcutone octatonic: Replacing the G with the G# changes the mode of the Porcupine[7] scale represented, and replaces diatonic with harmonic minor modes for the Meantone[7] scale represented, now a MODMOS.

On D we get the scale:

174.055 320.69 557.888 704.524 878.579 1025.214 1199.269 on the notes D E F G# A B C D

We get the following 7 modes of porcutone harmonic minor scale:

  • Mode 3: Lsmsmms Lydian ♯2 bright major
  • Mode 2: mmsLsms Ionian ♯5 symmetric minor
  • Mode 1: msLsmsm Ukranian dorian bright minor
  • Mode 0: sLsmsmm Phyrgian dominant dark major
  • Mode -1: msmmsLs harmonic minor dark diminished
  • Mode -2: smmsLsm Locrian ♮6 bright diminished
  • Mode -3: smsmmsL altered diminished magical seventh

Using an Ab instead, we get the scale:

174.055 320.69 494.745 641.38 878.579 1025.214 1199.269

Which has porcutone harmonic major modes:

  • Mode 3: Lsmmsms Lydian Augmented ♯2 bright major
  • Mode 2: msLsmms Lydian ♭3 bright minor
  • Mode 1: sLsmmsm Mixolydian ♭2 dark major
  • Mode 0: mmsmsLs harmonic major bright diminished
  • Mode -1: msmsLsm Dorian ♭5 dark diminished
  • Mode -2: smsLsmm Phrygian ♭4 symmetric minor
  • Mode -3: smmsmsL Locrian magical ♭♭7

Porcutone pentatonic

Ok we’re almost done:

We just have our major and minor pentatonics left!

On F# the major pentatonic is 209.779 383.834 704.524 878.579 1199.269

~ 9/8 5/4 3/2 5/3 2/1 msLsL. Tempers to ssLsL for Meantone[5], LsLsL for Father[5], and sLLLL for Bug[5].

The same scale is also available on G.

Tunings

We could tune the scale in many different ways. The TE tuning given above consists of 7 large steps of 146.6352c, 1 medium step of 63.1434c, and 4 small steps of 27.4197c.

We could instead tune to POTE no-7 ptolemismic, resulting in a very similar 7L 1m 4s = (146.7247c, 63.1818c, 27.4363c).

For reference, the 5-limit JI tuning of (27/25, 25/24, 250/243) is equal to (133.2376c, 70.6724c, 49.1661c). There are also least squares and minimax. I hope to figure those out.

We could also tune to edos. Tuning to 15edo, 22edo or 29edo collapses the scale to a Porcupine[8] scale, and tuning to 19edo or 31edo tempers the scale to a Meantone[12] scale. We can retain three step sizes if we tune to 27edo (using 27e), 34edo, or to 41edo.

27edo: 7L 1m 4s = (3, 2, 1) = (133.3333c, 88.8889c, 44.4444c)

34edo: 7L 1m 4s = (4, 2, 1) = (141.1765c, 70.5882c, 35.2941c)

41edo: 7L 1m 4s = (5, 2, 1) = (146.3415c, 58.5366c, 29.2683c)

Chords

Porcutone diatonic

Since the scale is built from 6/5 3/2 9/5 2/1, it is the most readily available tetrad, containing a 4:5:6 major triad and a 10:12:15 minor triad. To tonal harmony we can use tertian chords in the diatonic scale, leading to:

  • D minor 10:12:15
  • E minor 10:12:15
  • F major 4:5:6
  • G major 4:5:6
  • A porcupine diminished / meantone minor 15:18:22
  • B diminished 25:30:36
  • C porcupine diminished / meantone major (has a neutral third) 27:33:40

Tertian tetrads:

  • D minor 7 10:12:15:18
  • E minor 7 10:12:15:18
  • F major 7 but it's actually a major neutral 7 chord 12:15:18:22
  • G porcupine major 7 / meantone dominant 7 20:25:30:36
  • A porcupine half-dim 7 / meantone minor 7 45:54:66:80
  • B half diminished 7 25:30:36:45
  • C porcupine half-dim 7 / meantone major 7 (has a neutral third) 27:33:40:50

9 chords:

  • D 10:12:15:18:22
  • E 33:40:50:60:72
  • F 36:45:54:66:80
  • G 20:25:30:36:45
  • A 45:54:66:80:100
  • B 25:30:36:45:54
  • C 27:33:40:50:60

11 chords:

  • D 30:36:45:54:66:80
  • E 33:40:50:60:72:90
  • F 36:45:54:66:80:100
  • G 20:25:30:36:45:54
  • A 45:54:66:80:100:120
  • B 25:30:36:45:54:66
  • C 27:33:40:50:60:72

13 chords:

  • D 30:36:45:54:66:80:100
  • E 33:40:50:60:72:90:108
  • F 36:45:54:66:80:100:120
  • G 20:25:30:36:45:54:66
  • A 45:54:66:80:100:120
  • B 25:30:36:45:54:66:80
  • C 27:33:40:50:60:72:90

Quartal chords:

  • D-G-C 15:20:27
  • E-A-D 11:15:20
  • F-B-E 24:33:44
  • G-C-F 11:15:20
  • A-D-G 9:12:16
  • B-E-A 15:20:27
  • C-F-B 6:8:11

D-G-C-F 15:20:27:36

D-G-C-F-B 30:40:54:72:99

Comma pump

We can't use our circle of fifths (Meantone comma pump) or our Porcupine comma pumps here, as both 81/80 and 250/243 are observed. In the ptolemismic tuning we temper out 100/99 which we can can pump with chord progressions such as

D-F-A-C -> F-A-C-E -> E-G-B-D -> D-F-A-C

D-F-A -> F-B-E -> (E-G-B) -> G-B-D -> D-F-A