Skeleton Jelly by Mat Brinkman

I am Skeleton Jelly. I am Skeleton Jelly. I am Skeleton Jell. I am Skeeton Jelly. I am Sketeton Jelly. I am Skeleton Jelly. 

My brain! ... is made ... of tiny ... animals!

... I am Skullton Jelly. I am Skulltown Jelly? No! I am Skelleton Jelly! I am Skeleton Jelly. I am Skeleton Jelly. 

Really? Somebody was just here looking for you.

Skeleton Jelly?

It said if it finds you it will tear you into pieces and eat them. 

I am gettin' eaten? I am Skeleton Eating? No! I am Skeleton Jelly. I am Skeletin Jelly. I am Skeleton Jelly. I am Skeleton Jelly. 

Well met! Have a drink.

Am I drinking jelly? Am I drunk on jelly? No, I am Skeleton Jelly! 

You are Skeleton Jelly? I've been looking for you!

I am Squirxical Jelly. I am Squirclixal Jelly. I am Squirxical Jelly. 

Where is your skeleton?

Die-jested.

Do you know where you are?

Citadel City?

Far from it. If you are not careful you will drip to the ruined Ultra Violet City.

Am I Careful Jelly?

Farther below...

Am I Dripping Jelly

Umm dripping to the ruined ultraviolet city?

Qutb al-Din al-Shirazi and the Systematists

Owen Wright is a scholar of medieval middle eastern music. In "The Modal System of Arabian and Persian Music 1250 to 1300", he writes extensively about music theorist Qutb al-Din, a prominent Systematist who wrote just after another prominent Systematist, writer Safi al-Din al-Urmawi, whose 17-tone Pythagorean gamut we've discussed before.

Qutb al-Din wrote extensively and he's a great source about medieval Persian and Arabic music of the time. In this post we'll be exploring his tetrachords (and pentachords and other ajnas) and modes, as relayed by Owen Wright.

Wright remarks that the modes of Qutb al-Din are notated twice, once in frequency ratios and once in pitches, and these are not consistent - clearly derived separately. The pitches weren't in Latin script, they were in Arabic I think, and they were a weird Pythagorean holdover notation from Qutb al-Din's predecessor Safi al-Din, but Owen Wright doesn't write the pitches in Arabic and neither will I. The fact that the frequency ratios and pitches are inconstent in Qutb al-Din's work makes it a little hard to be sure what al-Din is talking about, but it gets worse. Another complication is that the Systematists really like simple frequency ratios even when they weren't true-to-sound. It seems, from reading Wright, that they basically only use Pythagorean or super particular ratios as relative degrees in tetrachords. For example, the only super-particular frequency ratios between a just minor third 6/5 and a Pythagorean major second 9/8, are 7/6 and 8/7, and so when a Systematist needs an interval in that range, you can be pretty sure that they'll grab one of those two, regardless of whether it is sonically appropriate. There is a difference of 111 cents between 6/5 and 9/8, and if we only distinguish two ratios in that range, well, that's roughly a 37-cent granularity, which might be better than 24-EDO, but it's not amazing for nailing down intonation.

For some reason Wright shares the tetrachords in terms of cents instead of ratios, but since there aren't that many frequency ratios that are used by the Systematists, it's easy enough to figure out what arithmetic they're doing behind Wright's notation.

Here's a pentachord from Qutb al-Din as relayed by Wright. He calls it "24b shahnaz":

[G, Ad, Bb, Bd, C, Dd, D]

[139, 128, 49, 139, 128, 49] cents

The cents correspond to these relative frequency ratios:

    [13/12, 14/13, 36/35, 13/12, 14/13, 36/35]

Wright points out that these frequency ratios don't form a perfect fifth, but that they should (based on the pitches and other facts, I'm sure). As another example, many ajnas have what would be a neutral third based on the pitch notation, but the frequency ratios have the third at a just major third, 5/4 at 386 cents. This is indeed lower than a Pythagorean major third and thus more in the direction of neutral. And indeed there are arguments that some middle eastern musicians have used 5/4 as a neutral third at some points in history, as many musicians currently do in Turkey. Owen Wright knows all the medieval manuscripts though and says that 5/4 doesn't make sense, and any time 5/4 is written, it should really be interpreted as a true neutral third, as the pitches indicate, i.e. more like 330 to 370 cents. So there's another case where the frequency ratios are probably not correct, and we're better off looking at the pitches, but what a shame because we'd really like a precise rational intonation.

Wright provides his own plausible ranges of cents for each scale degree of the ajnas, presented in little ruler graphics. By measuring the pixels and taking midpoints, I can tell you that this is a prototypical intonation for a medieval shahnaz pentachord according to Owen Wright:

    [0, 147, 293, 348, 498, 642, 702]

And a decent representation of that might be

    [1/1, 12/11, 32/27, 11/9, 4/3, 13/9 or 81/56, 3/2]

My pixel measuring process is a little bit labor intensive, so I'm not going to provide Wright's intonation everywhere just yet, but I do want to present the Systematist frequency ratios and pitch classes. Partly, these ratios are what was actually written, and I think there is some import to transmitting the history of the music theory veridically. Secondly, these frequency ratios still give us more clues about intonation than the naive 24-EDO interpretation of pitch classes, and I really want to know what the medieval modes sounded like and how they've evolved into modern ones. 

...


* Zirafkand-i Kuchek (or Zirafkand, or Kuchek, or Mukhalifak).

Pitches: [G, Ad, Bb, Bd]. // G and Bd are prominent notes.

Absolute: [1/1, 13/12, 7/6, 6/5]

Relative: [13/12, 14/13, 36/35] _ [139, 128, 49]

// Given by Safi al-Din as [14/13, 13/12, 36/35].


* 'Iraq:

Pitches: [G, Ad, Bd] // G and Bd are prominent notes.

Absolute: [1/1, 10/9, 5/4]

Relative: [10/9, 9/8]


* Zawli:

Pitches: [G, A, Bd] // G and Bd are prominent notes.

Absolute: [1/1, 9/8, 5/4]

Relative: [9/8, 10/9]


* Rahawi:

Pitches: [G, Ad, Bb, B] // G is the only prominent pitch.

Absolute: : [1/1, 13/12, 7/6, 5/4]

Relative: [13/12, 14/13, 15/14] _ [139, 128, 119]


* 'Ushshaq:

Pitches: [G, A, B, C] // G is the only prominent pitch.

Absolute: [1/1, 9/8, 81/64, 4/3]

Relative: [9/8, 9/8, 256/243]


* Busalik:

Pitches: [G, Ab, Bb, C] // G is the only prominent pitch.

Absolute: [1/1, 256/243, 32/27, 4/3]

Relative: [256/243, 9/8, 9/8]


* Nawa:

Pitches: [G, A, Bb, C] // No prominent pitch listed.

Absolute: [1/1, 9/8, 32/27, 4/3]

Relative: [9/8, 256/243, 9/8]


* Rast:

[G, A, Bd, C] // G is the prominent pitch.

[1/1, 9/8, 5/4, 4/3]

[9/8, 10/9, 16/15] _ [204, 182, 112]


* Nawruz:

Pitches: [G, Ad, Bb, C] // G and C are prominent.

Absolute: [1/1, 16/15, 32/27, 4/3]

Relative: [16/15, 10/9, 9/8] _ [112, 182, 204]


* 'Iraq (or Ru-yi 'Iraq):

Pitches: [G, Ad, Bd, C] // G and C are prominent.

Absolute: [1/1, 10/9, 5/4, 4/3]

Relative: [10/9, 9/8, 16/15] _ [182, 204, 112]


* Isfahan:

Pitches: [G, Ad, Bb, B, C] // G and C are prominent.

Absolute: [1/1, 13/12, 7/6, 5/4, 4/3]

Relative: [13/12, 14/13, 15/14, 16/15] _ [139, 128, 119, 112]

Here Owen Wright stops us to say that the frequency ratios for jins Isfahan and and the related jins Rahawi are unbelievable, and that the pitch notation is more accurate. Further he notes that jiins Isfahan is clearly derived by adding a major third within jins Nawruz.

I think it's time we looked a little more closely at jins Isfahan, jins Rahawi, and jins Nawruz. From the frequency ratios

    Rahawi has Bb at 7/6

    Isfahan has Bb 7/6

    Nawruz has Bb at 32/27

But from Owen Wright's ruler diagrams, it's clear he thinks that all three are Pythagorean on the chromatic intervals including the Bb, so Rahawi is:

    [1/1, ?, 32/27, 4/3]

By eye, it's obvious that Wright's intonation on the second scale degree, the {Ad}, is not much more precise than "some kind of neutral second". I'm tempted to use 13/12, since it's the ratio of the second scale degree used by Qutb al-Din in both jins Isfahan and jins Rahawi. On the other hand, Qutb al-Din uses 16/15 for the second scale degree of Nawruz, which is quite a bit lower, and so maybe we should use 14/13 as a compromise. But I'm not really feeling that. Let's use 13/12 for all of them. Or at least for Rahawi and Isfahan.

Lots of modern middle eastern music theorists, at in the xenharmonic parts I frequent, are very pleased with the idea that Isfahan as a tetrachord is tuned to [12:13:14:15:16]. And since that's how Qutb al-Din described it, ... maybe that's a fine way to play it? I don't know for sure if it's a medieval intonation, but if someone in modern times plays Isfahan like that, I won't be upset. I don't think I've ever seen anyone extend it all the way to a pentachord as 

    [13/12 * 14/13 * 15/14  * 16/15 * 17/16 * 18/17]

In absolute terms that would be

    [1/1, 13/12, 7/6, 5/4, 4/3, 17/12, 3/2]

Maybe no one adds in the tritone because they care more about history than about playing a harmonic series. Anyway, let's keep looking at more ajnas.

* Hijazi:

Pitches: [G, Ad, B, C] // G and C are prominent.

Absolute: [1/1, 12/11, 14/11, 4/3]

Relative: [12/11, 7/6, 22/21] _ [150, 267, 81]

Owen wright says that the major third was probably not sharper than major thirds of other genera, but otherwise he's happy with the ratios:

    "This minor adjustment apart, Hijazi is one of the rare cases in which the ratios for a theoretical non-diatonic genus would seem to correspond exactly to intervals used in practice." 

Super hot fire, Owen. Way to stick it to the Systematists frequency ratios. Although there are only three relative ratios in the tetrachord, and if we're changing the intonation of the 3rd scale degree, then we have to fiddle with two of them, so is this really any kind of praise? Even at his most congratulatory, Wright is basically saying "Way to get a single frequency ratio right, Qutb." 

Anyway, I think this is what Owen Wright would condone for Hijazi:

    [G, Ad, B, C]

    [1/1, 12/11, 81/64, 4/3] _ [0, 151, 408, 498]

    [12/11, 297/256, 256/243] _ [151, 257, 90]

This looks kind of weird to me as a modern intonation for jins Hijaz, but maybe it's a medieval one, sure.

Now we get some pentachords

* 'Ushshaq pentachord:

[G, A, B, C, D] // G is prominent.

[9/8, 9/8, 256/243, 9/8]


* Busalik pentachord:

[G, Ab, Bb, C, D] // G and D are prominent.

[256/243, 9/8, 9/8, 9/8]

Which just add an AcM2 onto the tetrachord of the same name. We also get a pentachord version of the Nawa tetrachord:

[G, A, Bb, C, D]

[9/8, 256/243, 9/8, 9/8]

This jins was mentioned in the "Kitab al-Adwar" by Safi al-Din but not in works by Qutb al-Din, who is normally the more comprehensive source. Apparently this jins doesn't have a historic name, but I think "Nawa Pentachord" suits it just fine. But also, who cares about pentachords that are just tetrachords with AcM2 added on the top. Boring.

* Rast pentachord:

    [G, A, Bd, C, D]

    Absolute: [1/1, 9/8, 5/4, 4/3]

    Relative: [9/8, 10/9, 16/15, 9/8]

* Isfahan-i Asl pentachord (also called Mukhalif-i Rast):

[G, A, Bd, C, C#, D] // G and D are prominent.

        Absolute: [1/1, 9/8, 39/32, 21/16, 45/32, 3/2]

Relative: [9/8, 13/12, 14/13, 15/14, 16/15]

Owen wright points that this is an Isfahan tetrachord with AcM2 added at the bottom instead of the top. Mukhalif (or mukhtalif) means "differing" in Arabic, like saying "the other/alternative Rast pentachord. It's worth noticing that these two scales having very different frequency ratios but very similar pitches. You can decide for yourself if this is another point against the frequency ratios or evidence of different intonation for the tones across different ajnas. I will say that 21/16 at 470 cents is noticeably flat of a normal C natural over G at 498 cents, and that the author might have added an accidental to the pitches to drawn attention to this 28 cent difference, which is not really a subtle thing. Although I did mention that Systematists sometimes only have like a 37-cent granularity. I still think someone would have mentioned an impure P4, since pure perfect fourths were maybe considered the highest consonance in medieval middle eastern music.

...

I'm sad and tired.

...

* Husayni pentachord

[G, Ad, Bb, C, D] # G and D are prominent notes.

[1/1, 16/15, 32/27, 4/3, 3/2]

[16/15, 10/9, 9/8, 9/8] _ [112, 182, 204, 204]

* Zirkesh Huseyni pentachord:

[G, Ad, Bb, B, C, D] # G and D are prominent notes.

[1/1, 13/12, 7/6, 5/4, 4/3, 3/2]

[13/12, 14/13, 15/14, 16/15, 9/8] _ [139, 128, 119, 112, 204]

* Buzurg of Safi al-Din (or Buzurg-i Asl of Qutb al-Din):
[G, Ad, (Bd), C, C#, D] # G and D are prominent notes.
[1/1, 14/13, 16/13, 4/3, 56/39, 3/2]
[14/13, 8/7, 13/12, 14/13, 117/112] _ [128, 231, 139, 128, 76]

* Variant of Buzurg:
[G, Ad, B, C, C#, D] # G and D are prominent notes.
[1/1, 12/11, 14/11, 4/3, 56/39, 3/2]
[12/11, 7/6, 22/21, 14/13, 117/112] _ [150, 267, 81, 128, 76]

...

I'm getting a little bit sad with these ajnas. The frequency ratios are all wrong. I should just list the pitches and be done.

There are pages and pages of more ajnas in the Owen Wright reference. But let's go over what we've already seen a bit.

Three Pythagorean tetrachords:
[M2, M2, m2]: 'Ushshaq // Modern jins 'Ajam 
[M2, m2, M2]: Nawa // Modern jins Nahawand
[m2, M2, M2]: Busalik // Modern jins Kurdi

Three tetrachords that mix neutral seconds with a major second:
[M2, n2, n2]: Rast // Modern jins Rast
[n2, M2, n2]: Ru-yi 'Iraq // Modern jins Huseyni or jins 'Iraq 
[n2, n2, M2]: Nawruz // Modern jins Bayyati

Two funny tetrachords:
[n2, n2, A1, m2]: Isfahan
[n2, M3 - n2, m2]: Hijazi

For ajnas that span less than P4, we have

[n2, M2]: 'Iraq
[M2, n2]: Zawli
[n2, n2, n3 - m3]: Zirafkand
[n2, n2, m2]: Rahawi

I don't have a name for intervals like [n3 - m3] in the shorthand where I use {n} for neutral intervals, but they happen to fall between P1 and A1 in just tuning, so I guess we could call them neutral unisons, {n1}. These can be generated by subtracting our favorite neutral seconds from a major second:

9/8 / (14/13) = 117/112
9/8 / (13/12) = 27/26
9/8 / (12/11) = 33/32
9/8 / (11/10) = 45/44

Almost all super particular. Nice. This notion of a neutral unison makes several other things more compact or sensible. I had written the middle relative degree of jins Hijazi as [M3 - n2], but we could also write it as [M2 + n1], which is more obviously a kind of 2nd interval. Also the 32/27 complements of Zalzalian neutral seconds can be succinctly written as [m2 + n1], e.g.

    (256/243) * (27/26) = 128/117 (The 32/27 complement of 13/12)
    (256/243) * (33/32) = 88/81  (The 32/27 complement of 12/11)

And I think that's nice too.

...

I think I'm going to skip to modes.

'Ushshaq: [G, A, B, C, D, E, F, G] : [M2, M2, m2] + [M2, M2, m2] +  M2
Busalik: [G, Ab, Bb, C, Db, Eb, F, G] : [m2, M2, M2] + [m2, M2, M2] + M2 
Nawa: [G, A, Bb, C, D, Eb, F, G] : [M2, m2, M2] + [M2, m2, M2] +  M2
Rast: [G, A, Bd, C, D, Ed, F, G] : [M2, n2, n2] + [M2, n2 n2] + M2
'Iraq: [G, Ad, Bd, C, Dd, Ed, F, F#, G] : [n2, M2, n2] + [n2, M2, n2] [A1 + m2]
Isfahan: [G, A, Bd, C, D, Ed, F, F#, G] : [M2, n2, n2] + M2 + [n2, n2, A1, m2]
Rahawi: [G, Ad, Bd, C, Dd, Eb, F, G] : [n2, M2, n2] + [n2, n2, M2] + M2
Hijazi version 1: [G, Ad, Bb, C, Dd, Ed, F, G] : [n2, n2, M2] : [n2, M2, n2] + M2
and/or 
Hijazi version 2: [G, Ad, Bd, C, Dd, Ed, F, G] : [n2, M2, n2] + [n2, M2, n2] + M2
Husayni: [G, Ad, Bb, C, Dd, Eb, F, G] : [n2, n2, M2] + [n2, n2, M2] + M2

Here are the same pitches with briefer tetrachord analyses:

'Ushshaq: [G, A, B, C, D, E, F, G] : Ushshaq + Ushshaq + T
Busalik: [G, Ab, Bb, C, Db, Eb, F, G] : Busalik + Busalik + T
Nawa: [G, A, Bb, C, D, Eb, F, G] : Nawa + Nawa + T
Rast: [G, A, Bd, C, D, Ed, F, G] : Rast + Rast + T
'Iraq: [G, Ad, Bd, C, Dd, Ed, F, F#, G] : 'Iraq + 'Iraq + [A1 + m2]
Isfahan: [G, A, Bd, C, D, Ed, F, F#, G] : Rast + T + Isfahan
Rahawi: [G, Ad, Bd, C, Dd, Eb, F, G] : 'Iraq + Nawruz + T
Hijazi version 1: [G, Ad, Bb, C, Dd, Ed, F, G] : Nawruz + 'Iraq + M2
Hijazi version 2: [G, Ad, Bd, C, Dd, Ed, F, G] : 'Iraq + 'Iraq + M2
Husayni: [G, Ad, Bb, C, Dd, Ed, F, G] : Nawruz + Nawruz + M2

Here are some weirder modes that I'm gradually analyzing intervallically:

Buzurg: [G, Ad, B (or Bd), C, C#, D, E, Ft, G]  : [n2, M2 + n1 (or M2), m2 (or n2), A1, m2, M2, n2, n2] // Something like Hijazi + T + Rast, but with an extra C# and and also the weirdness about the variable third interval meaning that the first tetrachord might be 'Iraq.  
Zankula: [G, A, Bd, C, Dd, Ed, F, (F#), G] : [M2, n2, n2, n2, M2, n2, M2 (or A1, m2)] // jins Rast + jins Iraq + T, and you can add in a leading tone at to the high octave if you want. This one isn't so crazy.
Zirafkand: [G, Ad, Bb, C, Dd, Eb, Ed, Ft, G] : [n2, n2, M2, n2, n2, n1, M2, n2]// This one is genuinely crazy.

Kardaniya: [G, A, Bd, C, C#, D, E, Ft, G] : [M2, m2, M2, A1, m2, M2, n2, n2] // Almost jins Nawa + T + jins Rast, except the tone is split into [A1, m2].  
Kawasht: [G, Ad, Bd, C, Dd, Eb, Ed, Ft, G] : [n2, n2, M2, n2, n2, n1, M2, n2] // Genuinely crazy.
Nawruz: [G, Ad, Bb, C, Dd, Eb, F, ?(G)] : [n2, n2, M2, n2, n2, M2, ?(M2)] // jins Nawruz + jins Nawruz + ?(T). Not crazy at all, except I'm not sure that this one hits the octave.
Maya: [G, Bb, C, Eb, F] : [m3, M2, m3, M2] # Not interesting, not really a scale, maybe just someone's favorite melody?
Shahnaz: [G, Ad, Bb, Bd, Ab, G] : [n2, n2, n1, -(M2 + n1), -m2] // Ascends and descends, not really a scale.
Salmak: [G, A, B, Ct, D, Eb] : [M2, M2, n2, n2, m2] // Whatever.

Anyway, lots of conjunct tetrachords in the medieval modes.

...

Somehow I'm more curious which of these modes matches modern Persian Dastgah-ha than modern Arabic maqamat. Let's have a look. I'm going to hope that all of the modes presented by Owen Wright actually have the tonic on the starting note G.


Qutb's mode Ushshaq looks like Dastgah Rast-Panjgah if you just look at the intervals for each scale degree, although they have different tetrachord structures. Qutb's mode Busalik is a cyclic permutation of Rast-Panjgah and so is Qutb's mode Nawa. Qutb's mode Rast is a cyclic permutation of Dastgah Shur. Qutb's mode 'Iraq is very similar to Dastgah Chahargah, but they have different intonation, and Chahargah has a parallel disjunct tetrachord structure while 'Iraq is conjunct. Qutb's mode Isfahan has the same lower tetrachord and disjunct tone as the Persian Bayat-e Esfahan, but Qutb's version has a 5-note tetrachord at the top while Bayat-e Esfahan has a 4-note dang Chahargah as its upper tetrachord, which is more like the Hijazi tetrachord. Qutb's mode Rahawi does not seem to have any correspondence in the modern Persian Dastgah. Hijazi is also related to Chahargah. Qutb's mode Huseyni doesn't seem to correspond to anything in modern Persian Dastgah.

...

Some 23-limit Otonal Tetrachords

I'll might write in descriptions of these at some point comparing them to ancient Greek and modern Persian/Arabic/Turkish tetrachords. But for now, here are some otonal representations of tetrachords:

[9, 10, 11, 12] [1/1, 10/9, 11/9, 4/3] [P1, M2, AsGrm3, P4]

[12, 13, 14, 16] [1/1, 13/12, 7/6, 4/3] [P1, Prm2, Sbm3, P4]

[12, 13, 15, 16] [1/1, 13/12, 5/4, 4/3] [P1, Prm2, M3, P4]

[15, 16, 18, 20] [1/1, 16/15, 6/5, 4/3] [P1, m2, m3, P4]

[15, 17, 18, 20] [1/1, 17/15, 6/5, 4/3] [P1, ExM2, m3, P4]

[18, 19, 21, 24] [1/1, 19/18, 7/6, 4/3] [P1, Lfm2, Sbm3, P4]

[18, 19, 22, 24] [1/1, 19/18, 11/9, 4/3] [P1, Lfm2, AsGrm3, P4]

[18, 19, 23, 24] [1/1, 19/18, 23/18, 4/3] [P1, Lfm2, NbM3, P4]

[18, 20, 21, 24] [1/1, 10/9, 7/6, 4/3] [P1, M2, Sbm3, P4]

[18, 20, 22, 24] [1/1, 10/9, 11/9, 4/3] [P1, M2, AsGrm3, P4]

[18, 20, 23, 24] [1/1, 10/9, 23/18, 4/3] [P1, M2, NbM3, P4]

[21, 24, 26, 28] [1/1, 8/7, 26/21, 4/3] [P1, SpM2, PrSpGrm3, P4]

[21, 24, 27, 28] [1/1, 8/7, 9/7, 4/3] [P1, SpM2, SpM3, P4]

[21, 25, 26, 28] [1/1, 25/21, 26/21, 4/3] [P1, SpA2, PrSpGrm3, P4]

[21, 25, 27, 28] [1/1, 25/21, 9/7, 4/3] [P1, SpA2, SpM3, P4]

[24, 26, 28, 32] [1/1, 13/12, 7/6, 4/3] [P1, Prm2, Sbm3, P4]

[24, 26, 30, 32] [1/1, 13/12, 5/4, 4/3] [P1, Prm2, M3, P4]

[24, 27, 28, 32] [1/1, 9/8, 7/6, 4/3] [P1, AcM2, Sbm3, P4]

[24, 27, 30, 32] [1/1, 9/8, 5/4, 4/3] [P1, AcM2, M3, P4]

[27, 28, 32, 36] [1/1, 28/27, 32/27, 4/3] [P1, Sbm2, Grm3, P4]

[27, 30, 32, 36] [1/1, 10/9, 32/27, 4/3] [P1, M2, Grm3, P4]

[27, 30, 33, 36] [1/1, 10/9, 11/9, 4/3] [P1, M2, AsGrm3, P4]

[27, 30, 34, 36] [1/1, 10/9, 34/27, 4/3] [P1, M2, ExGrM3, P4]

Maqam Sikah Baladi

Maqam Sikah Baladi is an Arab maqam (rather than Turkish or Persian) with a lot of microtones. We're going to try figuring out some things about it.

MaqamWorld decsribes an associated scale fragment, jins Sikah Baladi, as:

    [Ed, Ft, G, Ad, Bd, C] 

Those are the base pitch classes that would indicate 24-EDO steps, but they have some extra accidentals that I haven't transcribed.

The Ed is flatter than 24-EDO, the Ft is sharper, the Ad is flatter, the Bd is sharper, and the C is flatter.

If we ignore those extra accidentals, I would notate this in 24-EDO steps as:

    [4, 3, 3, 4, 3]\24

If we include the accidentals, we'll have to commit to some kind of step size for the flattening and sharpening. Let's arbitrarily call it 0.25 steps. If it was more than 0.5 steps, then we'd be closer to the next step and the pitches would have been notated differently. With that intonation, we get this for our steps:

    [4.5, 2.75, 2.75, 4.5, 2.5]\24.

MaqamWorld says that the tonic/finalis is on G, and that there is no ghammaz.

Oud player Joseph Tawadros describes maqam sikah baladi as 

    [C, Dd, Ed, Ft, G, Ad, Bd, C]

in a Facebook video. The jins sikah baladi from MaqamWorld is a subset of this, so that's a nice bit of agreement. In 24-EDO these pitch classes are:

    [0, 3, 7, 11, 14, 17, 21, 24] // relative

    [3, 4, 4, 3, 3, 4, 3] // absolute

with the initial [3, 4] being the relative intervals not accounted for in the jins. And those are the intervals of the normal jins Sikah, so everything looks good so far.

Now let's compare to maqam Sikah Baladi from MaqamWorld. They have it written descending, and I'm sure it's played in a descening way, but I like to write my scales ascending and will do so now.

The maqam starts low with part of jins Sikah baladi (starting in te middle at the tonic on G) and moving up tot that flat C like beofre:

    [G, Ad, Bd, C]

Then there's a C# as part of jins "pseudo-hijazkar / suspended 5th"

The pitch classes of this are

    [C#, D, Ed, Ft, G]

From the pitch classes, we'd expect this to have an 24-EDO intonation like

    [2, 3, 4, 3]

Agai    n this has non-24-EDO accidentals, indicating a flat Ed and a sharp Ft. If we use the 0.25 step intonation again, then we get

    [2, 2.75, 4.5, 2.75]

Let's compare this jins "pseudo-hijazkar / suspended 5th" to regular jins hijazkar.

MaqamWorld presents jins Hijazkar in terms of major tones as

    [3/2, 1/2, 1/2, 3/2] tones

i.e.

    [6, 2, 2, 6]\24

with pitches

    [Ab, B, C, Db, E, F] 

and notes that the C in the middle is the tonic and there is no ghammaz. That looks absolutely nothing like pseudo-hijazkar.  It doesn't even have neutral tones. I think we just have to ignore that jins label.

Let's continue on with the maqam from MaqamWorld. Overlapping with jins pseudo-hijazkar we have another jins Sikah Baladi, this time the standard one that stretches from a flat Ed up to a flat C. I will note that there are numbers 1 through 7 starting under the D and moving up to the high C, as through D is the tonic of the whole maqam and it doesn't reach the octave, and the C# in the middle is just a leading tone up to the D.

I'm tempted to ignore the low jins Sikah Baladi since 

    1) it doesn't give as any new information (being repeated above),   

    2) it messes up the intervallic structure when we have both C natural and C#, and 

    3) The tetrachord doesn't even present in full, only including from G up to C instead of from Ed up to C.

If we skip all the notes from the lowest jins, then our maqam Sikah Baladi loos like this:

    [(C#), D, Ed, Ft, G, Ad, Bd, C]

Using the same intonation for the non-24-EDO accidentals, this would look like 

[(2), 2.75, 4.5, 2.75, 2.75, 4.5, 2.5]\24.

in relative steps, which is an adjusted version of this:

[(2), 3] + [4, 3, 3, 4, 3] \24

Across the whole maqam, including the lower jins Sikah Baladi, the notes which are highlighted as special targets for tonicization and/or ghammazization are [G, Bd, D, G, Bd]. So I don't know why people ever present the scale spanning from C to C.

The maqam Sikah Baladi of Tawadros reaches the octave and has Dd instead of D, but is otherwise quite close.

If we altered the MaqamWorld version of the maqam so that we had a tonic of a 0.25-step-flattened C natural (instead of a leading tone of C#), then the maqam would be:

    [4.25, 2.75, 4.5, 2.75, 2.75, 4.5, 2.5]\24.

which does reach the octave. This still differs from Tawadros's maqam in having D natural instead of Dd, but there's more agreement than disagreement.

Navid from OudForGutarists posted a piece in Sikah Baladi with key signature [Ad, Ed, Bd, Ft], which is consistent with these pitches:

    [C, D, Ed, Ft, G, Ad, Bd, C]

He starts his phrases on Ed, works up to a few notes to G, and ten works down to a low G where he ends his phrases, so it's more like

    [G, Ad, Bd, C, D, Ed, Ft, G]

Anyway, with two sources agreeing on D instead of Dd, I'm going to go with that.

One more data source? There are some video on youtube from user @FantasticoTube that maqamat and look like they're from a website that has gone defunct. Honestly, they look like an early version of MaqamWorld, but perhaps they're unrelated. The FantasticoTube video presents Sikah Baladi twice. The first form looks like this:

    [G, Ab, B, C, D, Eb, F#, G]

    [1/2, 3/2, 1/2, 1, 1/2, 3/2, 1/2] tones

with arrow accidentals indicating that Ab is played sharper, B is played flatter, Eb is played sharper, and F# is played flatter. Tetrachord annotations describe it as 

    [Hijaz on G + major second + Hijaz on D]

The second form looks like this:

    [G, Ad, Bd, C, D, Ed, Ft, G]

   [3/4, 1, 3/4, 1, 3/4, 1, 3/4] tones

It is annotated with jins as 

    [Sikah on G] + 3/4 + 1 + 3/4 + [Sikah on D]

This version with quarter tones and jins Sikah does indeed move the maqam in the direction indicated by the arrow accidentals from the first form.

So the idea seems to be to alter jins hijaz

    [2, 6, 2]\24

by quarter tones to give 

    [3, 4, 3]\24

which has its first wo intervals the same as a 24-EDO jins Sikah, although this guy here is an actual tetrachord whereas the traditional jins Sikah is just a trichord.

Anyway, the second form form of maqam Sikah Baladi from FantasticoTube has the same pitch classes and arrangement as my summary of Navid's maqam Sikah Baladi ending on G:

    [G, Ad, Bd, C, D, Ed, Ft, G]

So now we've got tons of agreement. Here it is in integer steps of 24 EDO:

    [3, 4, 3, 4, 3, 4, 3]\24

Using the sub-quarter tone intonation inspired by notes from MaqamWorld (still with 0.25 steps unless you've got a better idea), this is our more precise intonation given this arrangement of pitch classes:

    [G (2.75) Ad (4.5) Bd (2.5) C (4.25) D (2.75) Ed (4.5) Ft (2.75) G]

The 24-EDO version does indeed have a repeated structure with tetrachords that are like jins Hijaz adjusted toward jins Sikah:

    [3, 4, 3] + T + [3, 4, 3]

Although the repeated structure is less exact in my intonation with the made up 0.25 tone adjustments.

    [2.75, 4.5, 2.5] + [4.25] + [2.75, 4.5, 2.75]

I think this is a slight problem. If we adjust the intonation so that the lower group of three relative intervals sum a tempered P4 at 10 steps of 24-EDO, then we get C natural instead of the slightly flat C that MaqamWorld specifies. (The upper group of three relative intervals is already a true tetrachord spanning 10 steps).

I think we need more data to make more conclusions.

If we want to make a just tuning based on the 0.25 step intonation, here's one option:

[P1, Prm2, ReM3, HbAc4, P5, Prm6, ReM7, P8] # [1/1, 13/12, 16/13, 45/34, 3/2, 13/8, 24/13, 2/1] _ [0, 139, 359, 485, 702, 841, 1061, 1200] cents

[Prm2, ReReAcA2, HbPrAcm2, ExM2, Prm2, ReReAcA2, Prm2] # [13/12, 192/169, 585/544, 17/15, 13/12, 192/169, 13/12] _ [139, 221, 126, 217, 139, 221, 139] cents

It looks pretty good in absolute intervals and a little crazy in relative intervals. If we assume adjustments more like 12 cents, then this is a decent tuning:

[P1, AsGrm2, GrM3, HbAc4, P5, AsGrm6, GrM7, P8] # [1/1, 88/81, 100/81, 45/34, 3/2, 44/27, 50/27, 2/1] _ [0, 143, 365, 485, 702, 845, 1067, 1200]

[AsGrm2, DeAcA2, HbAcAcm2, ExM2, AsGrm2, DeAcA2, Acm2] # [88/81, 25/22, 729/680, 17/15, 88/81, 25/22, 27/25] _ [143, 221, 120, 217, 143, 221, 133]

Although I kind of doubt that the maker of MaqamWorld would even write a note about a difference of intonation as small as 12 cents.

We need more data to draw more conclusions.

...

OffTonic Theory! It's a website where a guy describes the use of Arabic maqamat in Syrian Jewish liturgical music. And the author of the site uses 53-EDO instead of 24 EDO. He analyzes the maqam as having a hijaz-like tetrachord at the base of either [6, 10, 6] or [7, 8, 7] relative steps. A frequency ratio between 8 and 10 steps of 53-EDO isn't all that precise - it's a 45 cent difference, but we can use this. We are not restricted to using integers. What's the intonation of Sikah Baladi? About [6.5, 9, 6.5], i.e. [147, 204, 147] cents relative or [0, 147, 351, 498] cents absolute. Those are actually surprisingly close to 24-EDO values of [0, 150, 350, 500] cents absolute or [3, 4, 3]\24 steps relative. So a 24-EDO intonation isn't too bad among Syrian Jews at least. A nice nearby just intonation for this is

    [1/1, 12/11, 27/22, 4/3] absolute

    [12/11, 9/8, 88/81] relative

A this one's a less simple but it's symmetric:

    [1/1, 12/11, 11/9, 4/3] absolute

    [12/11, 121/108, 12/11] relative

So there's another option for intonation, though I can't help but feel that the intonation I made up is better.

...

Ah! Got it.

Sami Abu Shumays gives a .scl file for a pitch set that includes Jiharkah and its modulations and says that jins Sikah Baladi is an option: https://tuning.ableton.com/arabic-maqam/jiharkah/. The tricky bit is that this Sikah Baladi has its tonic on C instead of G, so we'll have to transpose.

Here's our maqam Sikah Baladi from MaqamWorld:

    [G, low Ad, high Bd, low C, D, low Ed, high Ft, G]

Move that up P4 or down P5 and we get:

... nothing. Those pitches aren't in his pitch set. We'd be a lot closer if we hadn't transposed.

Rooting the maqam on G and using the closest available pitches for modulation, we get [G, Ab, Bd, C, D, E-, F#, G] -> [0, 123, 359, 498, 707, 876, 1088, 1200]. This looks plausible as an intonation (even if the pitch names aren't all correct) everywhere except for the E-, which should instead be a low E half flat instead of a low E natural. A low E half flat should be like 310 to 340 cents over C natural / perde Rast, so like 808 to 838 cents over G.

...

Oh, oops, he wasn't saying that maqam Sikah Baladi was a modulation option, just jins Sikah Baladi. So I shouldn't be looking for the full set of tones in the maqam. His intonation for just the jins  is: 

...

...

I asked the xenharmonic discord about the intonation of Sikah Baladi and Margo Schulter had an interesting take.

"The traditional interpretation might be like the versions of Systematist Buzurg from around 1300"

[1/1, 14/13, 16/13, 4/3] _ [0, 128, 359, 498] cents

[14/13, 8/7, 13/12] _ [128, 231, 139] cents

or

[1/1, 13/12, 26/21, 4/3] _ [0, 139, 370, 498] cents

[13/12, 8/7, 14/13] _ [139, 231, 128] cents

Buzurg (also called Buzurk, Buzrak, and Bozorg) is an difficult and interesting thing to pin down in the history of middle eastern music, but Margo Schulter is cool, so let's try.

Buzurg is, in one sense, a pitch or a perde or a place on the neck of a lute like a tanbur or oud. It's specifically an octave above perde Sikah. Thus if perde Rast is called C, then Sikah and Buzurg are both Ed, in different octaves.

Buzurg was also a mode in medieval Persian and Arabic music. My understanding is that Safi al-Din described the mode as 

    [P1, GrGrGrd3, GrGrd4, P4, GrGrGrd6, P5, AcM6, GrGrd8, P8] # [1/1, 65536/59049, 8192/6561, 4/3, 262144/177147, 3/2, 27/16, 4096/2187, 2/1] _ [0, 180, 384, 498, 678, 702, 906, 1086, 1200] cents

which is ugly due to being Pythagorean, but we give it a schismastic reinterpretation as:

    [P1, M2, M3, P4, Gr5, P5, AcM6, M7, P8] # [1/1, 10/9, 5/4, 4/3, 40/27, 3/2, 27/16, 15/8, 2/1]

    [M2, AcM2, m2, Ac1, AcM2, M2, m2] # [10/9, 9/8, 16/15, 10/9, 81/80, 9/8, 10/9, 16/15]

This is much nicer looking, it's spelled correctly intervallically (except for having two 5th intervals), and it's aurally indistinguishable from the previous intonation.

It's also basically just a major scale (with a weirdly doubled up 5th scale degree).

Encyclopedia Iranica says that the later Qoṭb-al-Dīn Šīrāzī in his "Dorrat al-tāj" provided corrections to Safi al-Din's work and gave a jins for Bozorg as a pentachord:

Absolute: [G, Ad, B, C, C#(+), D] _ [0, 150, 417, 498, 626, 702]

Relative: [150, 267, 81, 128, 76]

which can be extended with these tones:

Absoltue: [E, Gb, G] [204, 386, 498]

Relative: [204, 182, 112] cents

To give this full scale:

Full scale:

[G, Ad, B, C, C#(+), D, E, F#, G]

[0, 150, 417, 498, 626, 702, 906, 1088, 1200]

This has a fairly obvious detempering:

Absolute: [1/1, 12/11, 14/11, 4/3, 56/39, 3/2, 27/16, 15/8, 2/1]

Relative: [12/11, 7/6, 22/21, 14/13, 117/112, 9/8, 10/9, 16/15]

Although it's not spelled correctly in my interval naming system (with the 7/6 being a 3rd interval and the 22/21 being a 1st, though we'd hope for them to both be kinds of 2nds in order to get a scale that progressed alphabetically). That's fine. Not every medieval middle eastern music theorist will use my interval naming system.

The reference for that intonation in Encyclopedia Iranica is from Owen Wright. This definitely looks closer to a distinct middle eastern mode than Safi al-Din's garbage major scale, and it's closer to Margo Schulter's jins. I think both Safi al-Din and Qutb al-Din al-Shirazi have been described as being Systematists about middle eastern modes, not that I really know what that means (although I think they're the ones who introduced a [T B J]-like notation for tetrachords, and they might have championed 1/3 tones in contrast to quarter tones, and are they're probably involved any time you see an intonation involving 8/7 or 7/6), and they both lived around 1300 AD, so we are looking at "versions of Systematist Buzurg from around 1300", if you were curious.

Encyclopedia Iranica also lists some modern things called Bozorg across various middle eastern musical traditions. It's a shashmaqam in Tajikistan and Uzbekistan, "characterized by a pentatonic structure: (C) D E (F#) G A B (C) D." I don't know exactly what they mean by that, but it sure doesn't look anything like the microtonal scale of Qutb al-Din al-Shirazi. In modern Persian music, Bozorg is a melodic motif played in Dastgah Shur that goes through these notes [C, Dp, Eb, F, G, (Ap | Ab), Bb] but in a broadly descending order. This at least has a microtone or two. And it's also some other things. I don't know how these are connected and neither does Encyclopedia Iranica. It doesn't seem to be that they all emphasis a note that's an octave and a neutral third above Rast.

In modern Turkish music, Büzürk/Büzürg is a compound maqam described in ascending order as a "Buselik pentachord on A, a Huseyni pentachord on E, and a Çargâh pentachord on G." I'm sorry to say this is just Arel-Ezgi-Uzdilek bullshit and probably it can't tell us anything about the history of Buzurk, but let's try.

Genus Buselik is jins Nahawand, i.e. [9/8, 256/243, 9/8], and we can add on one more 9/8 for a pentachord. Huseyni is also called Ussak in Turkish music theory, but in Arabic it's called Bayati and has an intonation like [13/12, 128/117, 9/8] or [88/81, 12/11, 9/8]. Add on another 9/8 to get a pentachord. Finally Çargâh is the must infuriating name in all of the AEU corpus, because it's a Persian name for a tetrachord like Hijaz but they use it for Ajam, because they wanted a historic name for the major scale and to pretend like the western major scale was ever of central importance to their music, and their solution for that was .... to ignore history and change their own historic names. They already has Acem as a perde that was cognate with 'ajam. I get so mad when I see this, Hüseyin Sadeddin Arel. I curse you in your grave.

Anyway, jins 'Ajam is [9/8, 9/8, 256/243], and we can add on 9/8 for a pentachord. This doesn't look like any other Buzurg to my eye. I don't think it really even deserves to be called a "compound" maqam. It's just a seyr.

So, Buzurg. Is it related to Sikah Baladi? Yeah. Margo Schulter's 

    [14/13, 8/7, 13/12] and [13/12, 8/7, 14/13]

are both tuned to [6, 10, 6] steps of 53-EDO, like one of OffTonic Theory's intonations. It definitely looks like a modified jins Hijaz, and modified in the right direction.

Unlike my detempering of Bozorg from Qoṭb-al-Dīn Šīrāzī, Margo Schulter's tetrachord is spelled by 2nd intervals, which I really like. I think I slightly prefer her intonation with a leading 13/12, just based on it's similarity to my theoretical intonations for Sikah Baladi. If we make a maqam out of it, repeating the tetrachord with a AcM2 disjunction, we get:

    Absolute: [P1, Prm2, PrSpGrm3, P4, P5, Prm6, PrSpGrm7, P8] # [1/1, 13/12, 26/21, 4/3, 3/2, 13/8, 13/7, 2/1] _ [0, 139, 370, 498, 702, 841, 1072, 1200] cents

    Relative: [Prm2, SpM2, ReSbAcM2, AcM2, Prm2, SpM2, ReSbAcM2] # [13/12, 8/7, 14/13, 9/8, 13/12, 8/7, 14/13] _ [139, 231, 128, 204, 139, 231, 128] cents

...

Scansion Templates

3: Bali Hai | Edelweiss | Jingle Bells | In The Mood | J'attendrai | Rocket Man | Purple Rain | Choc'late Rain | Gagnam Style | Closing Time | You're So Vain

3: Girls Girls Girls | Hot Cross Buns | Three Blind Mice

3: The Space Pope | Free Fallin' | Chop Suey | Moon River


4: Hallelujah | Doctor Zaius | Sex And Violence  | Thunch And Snupple | O Susanna | Ol' Man River | Get Up, Stand Up. 

4: Five hundred miles | Abide with me | Where is my mind? | Come on, Eileen | All for me grog | Silver and gold | Eight Million Bees | All by myself | All Through The Night | Karma Police.


5: Anticipation | Eleanor Rigby | Eyyy, Macarena | Ooh, Barracuda | I'm Levitating | Guantanamera | She Drives Me Crazy

5: Autumn In New York | Blinded By The Light | Feliz Navidad | Puttin' On The Ritz | Smoke Gets In Your Eyes

5: Knights In White Satin

5: No, I Won't Back Down

5: Slip Slidin' Away

5: Take My Breath Away

5: The King Of The Road


6: And It's All For Me Grog

6: Caught In A Bad Romance | God Bless America | Hey Jude, Don't Make It Bad | 

6: How I Wish You Were Here

6: Please Don't Fear The Reaper | Sitting On A Park Bench | Some Enchanted Evening | Smile Like You Mean It

6: There's Whiskey In The Jar | We're Movin' Right Along


7: Ain't No Mountain High Enough | Blue Eyes Crying In The Rain | Button Up Your Overcoat | Camptown Races, Sing This Song | Diamonds Are a Girl's Best Friend | Dream A Little Dream Of Me | If I Only Had A Brain | Oh My Darling Clementine | Ain't No Sunshine When She's Gone | Ground Control To Major Tom | Going With Him Someday Soon | Help Me Make It Through The Night | Sunday Mornin' Comin' Down | Papa Was A Rodeo | I'm Not Sick But I'm Not Well | Twinkle Twinkle Little Star | While My Guitar Gently Weeps | Old McDonald Had A Farm | Hello Darkness My Old Friend

7: Someone To Watch Over Me | Stop Draggin' My Heart Around | It's Only A Paper Moon

7: Rudolph The Red Nosed Reindeer | Somewhere Over The Rainbow | I'm Leaving On A Jet Plane | A La Claire Fontaine 

8: All I Want for Christmas Is You | All We Are Is Dust In The Wind | But I Only Have Eyes For You


8: I'm Dreaming Of A White Christmas | Oh What A Beautiful Morning | O Lord, It's Hard To Be Humble

8: June Is Bustin' Out All Over | In The Hills Of Connemara

8: Lots Of Fun At Finnegan's Wake

8: Oh, Is There Not One Maiden Breast?

8: Teenage Mutant Ninja Turtles | Do You Want To Build A Snowman? | How Are Things in Glocca Morra? | Joyful Joyful We Adore Thee | Oh The Shark Has Pearly Teeth Dear

8: Well I Suppose, Anything Goes |  I'm Picking Up Good Vibrations

8: The Last Of Barrett's Privateers

8: The Night They Drove Old Dixie Down

8: Till All The Things You Are Are Mine


9: Ba Ba Black Sheep, Have You Any Wool

9: Beautiful Dreamer, Wake Unto Me

9: Blackbird Singing In The Dead Of Night

9: Give Me Some Afro-Cuban Bebop | I'll Never Be Your Beast Of Burden

9: Hush Little Baby, Don't Say A Word

9: I Am A Poor Wayfaring Stranger

9: I Bought Me A Cat, My Cat Pleased Me

9: I Know A Heartache When I See One

9: Just My Rifle, My Pony, And Me

9: Sing Us A Song You're The Piano Man

9: The First Time Ever I Saw Your Face

9: When I Take You Out In The Surrey

9: Whisper Words Of Wisdom, Let It Be


10: And Make A Northwest Passage To The Sea

10: And She's Buying A Stairway To Heaven

10: Buffalo Girls Won't You Come Out Tonight | It's The Most Wonderful Time Of The Year | But I Can't Help Falling In Love With You | Metal Movie Marijuana Meltdown

10: Even If We're Just Dancing In The Dark

10: Gather Up The Pots And The Old Tin Cans

10: I Don't Need To Walk Around In Circles

10: I Eat My Candy With The Pork And Beans

10: I Get Along Without You Very Well

10: I Have Emotional Motion Sickness

10: Night Time On The City Of New Orleans

10: People Say I've Got A Drinkin' Problem

10: Raindrops On Roses, Whiskers On Kittens

10: Summertime And The Living Is Easy

10: The Water Is Wide, I Can Not Cross O'er.

10: There Ain't No Way To Hide Your Lyin Eyes

10: We Will All Go Together When We Go


11: All The Other Kids With The Pumped Up Kicks

11: But Don't Look Back In Anger I Heard Her Say

11: Drop Kick Me, Jesus, Through The Goal Posts Of Life

11: I Gave My Love A Cherry That Had No Stone

11: I Want To Know Have You Ever Seen The Rain

11: If We Make It Through December, We'll Be Fine

11: Now You're Just Somebody That I Used To Know

11: Scarecrow & Fungus They Ran Through A Stoplight

11: The Lord Knows I'm Drinking And Running Around

11: Wearing Out Your Chompers Eatin' Goober Peas

11: You Can Hear The Whistle Blow A Hundred Miles


12: I Been Through The Desert On A Horse With No Name

12: Plenty Of Room At The Hotel California

12: Singing Me And Julio Down By The Schoolyard

12: That's Me In The Spot Light Losing My Religion

12: Yesterday All My Troubles Seemed So Far Away


13: Fly Me To The Moon And Let Me Play Amoong The Stars

13: Hey There, Delilah, What's It Like In New York City?

13: If You Don't Give Me Rye Whiskey I Surely Will Die


14: I Was Dancing With My Darling To The Tenessee Waltz

...

Georgian Folk Music

The country of Georgia has some great weird folk music. It often has pretty complex vocal polyphony. It's microtonal (and was even more microtonal before recent western influence). Some people will tell you it's based on a nearly equal heptatonic scale, i.e. 7-EDO. It doesn't sound like 7-EDO to me, but I haven't heard very much. Maybe I'm listening to the wrong sources.

So what is it? How is it tuned? I don't know. Let's figure it out.

Based on some spectral measurements in "Erkomaishvili Dataset: A Curated Corpus of Traditional Georgian Vocal Music for Computational Musicology" by (Rosenzweig, Scherbaum, Shugliashvili, Arifi-Müller, and Müller, 2020), I'd say a reasonable first start at describing the music would be a scale like this:

    [P1, M2, AsGrm3, P4, P5, M6, AsGrm7, P8] # [1/1, 10/9, 11/9, 4/3, 3/2, 5/3, 11/6, 2/1]

In relative degrees this is

    [10/9, 11/10, 12/11] * 9/8 * [10/9, 11/10, 12/11]

with the repeated tetrachord sized like

    [182c, 165c, 151c]

The scale, from the spectral analysis, clearly has a lower major second and major sixth than Pythagorean, and I've simply used the just tunings here. The scale also has neutral 3rds and 7ths. That's my first stab at it. Let's see what other have to say.

"The Georgian Musical System" (Malkhaz Erkvanidze, 2016) describes a Georgian scale that also has a repeated tetrachord structure. My introduction to Georgian folk music was a video of Malkhaz Erkvanidze singing in and directing a trio (https://www.youtube.com/watch?v=FVxD6NB8-CI) so I'm quite curious what he has to say about the genre.

The tetrachord he presents looks like this in cents:

    [172c, 154c, 172c]

Let's call this G for the Georgian tetrachord. This is a really weird tetrachord, especially since Georgians use harmonic instruments. If they had inharmonic bells and gongs it wouldn't be so crazy, but they sing and play strings and flutes and other harmonic instruments.

Let's try to figure out a just explanation for the tetrachord. The Georgian tetrachord looks like 7-EDO in-so-much as all of its steps are multiple of 171 cents, which the outer two intervals definitely are, but the middle step is not, and also the Erkvanidze source claims that in some scales the tetrachord appears twice alongside the usual Pythagorean acute major second at 9/8, so that we get an octave scale. How about these for just explanations:

[21/19, 12/11, 209/189] _ [173c, 151c, 174c]

[32/29, 35/32, 116/105] _ [170c, 155c, 172c]

I haven't worked much with 19-limit just intonation or beyond. I never thought there was much use for it. I hope Georgian music isn't 19-limit (or 29-limit). That would be kind of crazy. Or maybe it would be fun. I consider both of these tetrachords above to be perceptually indistinguishable from the Georgian tetrachord of Erkvanidze.

What's the just tuning of the full scale that has [G + AcM2 + G] as its tetrachord structure? If we use the 19-limit intonation of the G tetrachord, we get this scale:

    [1/1, 21/19, 252/209, 4/3, 3/2, 63/38, 378/209, 2/1]

If we use the 29-limit intonation, we get this scale:

    [1/1, 32/29, 35/29, 4/3, 3/2, 48/29, 105/58, 2/1]

I think the first one is ugly for its high complexity 3rd interval ratio and the second one is ugly for its high prime limit, but what can you do?

The paper goes on to describe some other scales that can be made with the Georgian tetrachord. We could have a scale that doesn't repeat at the octave like

    [G + G + AcM2 + G + G]

This spans 

    P4 + P4 + AcM2 + P4 + P4 = P8 + Grm7 = Grm14.

I almost wonder if I'm misunderstanding the paper's notation, such that the notated numbers aren't cents of frequency ratios, since the author simply uses [Bb, Eb] for the key signature in his staff notation, but that seems unlikely since the G tetrachord spans

    [172c + 154c + 172c] = 498c

just like a justly tuned P4.

...

Here's an idea! The ratio of 172c to 154c is very close to 8/7. If we want an EDO to represent both of these frequency ratios, we can do fairly well if it has a step around

    172c/8 = 21.5 cents

or

    154c/7 = 22 cents.

This means 55-EDO or 56-EDO. I think 56-EDO makes more sense. I don't think Georgian folk music is actually based on 56-EDO, but 56-EDO does a good job of representing Erkvanidze's tetrachord.

...

I can't help but wonder if the Erkvanidze came up with the Georgian tetrachord by saying, "our music sounds like 7-edo, but I want to describe it with a tetrachord structure; so which relative step of our scale can I mistune so that most of the frequency ratios are 1200/7 cents and one of them is 1200 * log_2(9/8) cents?". Maybe not. But it sure would parsimoniously explain the origin of a tetrachord that makes no sense unless you go to 19-limit.

On the other hand, I've heard that [C, F, G] is a very prototypical chord in Georgean music, i.e. Csus4 and Fsus2, and that kind of scans if they don't have particularly consonant 2nd, 3rd, 6th, or 7th intervals but they do have a nice P4 and P5.

...

Looking at figure 12 in "Analysis of the Tbilisi State Conservatory Recordings of Artem Erkomaishvili in 1966" by Scherbaum et al 2017, I would have guessed that the Georgian scale had a neutral sixth and a major 7th  

    [P1, M2, n3, P4, P5, n6, M7, P8]

instead of a major 6th and neutral seventh that I saw in "Erkomaishvili Dataset: A Curated Corpus of Traditional Georgian Vocal Music for Computational Musicology". Also in this source the Georgian intonation of P4 is shown to be a little sharp, like 18 cents over just. We can resolve the weirdness about which of 6th and 7th degree is neutral pretty easily: Erkvanidze tells us that Georgian music uses both disjunct and conjuct scales with the tetrachord repeated, i.e.

    [G + T + G] or [G + G + T]

So the previous scale could be analyzed as

    [10/9, 11/10, 12/11] * [10/9, 11/10, 12/11] * 9/8

and everything works out. Except for the slightly sharpened fourth, but I don't really care about that.

I think my superparticular tetrachord, [10/9, 11/10, 12/11], thus explains spectral data from multiple ethnographic papers, and it looks nicer than the 19-limit Georgian chord, and it's not a tetrachord I've seen in Arabic or Turkish or Persian music. It has a [Major, neutral, neutral] sound like a Arabic or medieval Ottoman rast, but those have an intonation more like

    [9/8, 11/10, 320/297] _ [204c, 165c, 129c]

so my version of the Georgian tetrachord

    [10/9, 11/10, 12/11] _ [182c, 165c, 151c]

has more equal frequency ratio sizes. Not quite 7-EDO equal, but audibly much closer to equal than Rast.

Now, I'm not positive that this is closer to the intonation of Georgian folk music than Erkvanidze's tetrachord. But it's beautiful and I hope it is. We've got three consecutive super particular ratios from the harmonic series spanning a fourth. In the disjunct tetrachord, with 9/8 below the upper tetrachord, we've got four consecutive super particulars. Makam Saba has a similar thing going on 

    [11/10, 12/11, 13/12, 15/13]

but not including 10/9, and one of Ben Johnston's scales has a similar thing going on, but in reverse

    [12/11, 11/10, 10/9, 9/8, 16/15, 15/14, 14/13, 13/12]

But the harmonic series isn't in reverse, so why not do it forwards? I think it's a very beautiful tetrachord.

The next thing for me to do is to listen to some hundred year old recordings of Georgian folk music and compare the sound to both my Georgian tetrachord and Erkvanidze's Georgian tetrachord.

...

Musical Wavelength Space

Suppose you've got a fretless string instrument and you want to place markers on the neck to help you find frequency ratios over open string frequencies. 

If you place a marker far from the sound hole so that 1/9 of the string is close to the tuning pegs and 8/9 of the string is free to vibrate when you pluck or bow or strum near the sound hole, the excited tone will have a frequency 9/8 over the frequency of the open string. If we put a marker there, I'll say that the marker is at 1/9 of the string length, meaning that 8/9 of the string is left free to vibrate.

The string length 8/9 and the frequency ratio 9/8 are reciprocal fractions, and this isn't a coincidence. Delightfully, the function that transforms 1/9 into 9/8 is also an involution, i.e. it can transform in both ways.
    y = x / (x - 1)
    frequency_ratio = (string_division) / (string_division - 1) 
    string_division = (frequency_ratio) / (frequency_ratio - 1)

If we divide the string into simple units, what simple frequency ratios do we get? Here's a little table

25.0 -> 25/24 _ 71c
24.5 -> 49/47 _ 72c
24.0 -> 24/23 _ 74c
23.5 -> 47/45 _ 75c
23.0 -> 23/22 _ 77c
22.5 -> 45/43 _ 79c
22.0 -> 22/21 _ 81c
21.5 -> 43/41 _ 82c
21.0 -> 21/20 _ 84c
20.5 -> 41/39 _ 87c
20.0 -> 20/19 _ 89c
19.8 -> 99/94 _ 90c
19.6 -> 98/93 _ 91c
19.5 -> 39/37 _ 91c
19.4 -> 97/92 _ 92c
19.2 -> 96/91 _ 93c
19.0 -> 19/18 _ 94c
18.8 -> 94/89 _ 95c
18.6 -> 93/88 _ 96c
18.5 -> 37/35 _ 96c
18.4 -> 92/87 _ 97c
18.2 -> 91/86 _ 98c
18.0 -> 18/17 _ 99c
17.8 -> 89/84 _ 100c
17.6 -> 88/83 _ 101c
17.5 -> 35/33 _ 102c
17.4 -> 87/82 _ 102c
17.2 -> 86/81 _ 104c
17.0 -> 17/16 _ 105c
16.8 -> 84/79 _ 106c
16.6 -> 83/78 _ 108c
16.5 -> 33/31 _ 108c
16.4 -> 82/77 _ 109c
16.2 -> 81/76 _ 110c
16.0 -> 16/15 _ 112c
15.8 -> 79/74 _ 113c
15.6 -> 78/73 _ 115c
15.5 -> 31/29 _ 115c
15.4 -> 77/72 _ 116c
15.2 -> 76/71 _ 118c
15.0 -> 15/14 _ 119c
14.8 -> 74/69 _ 121c
14.6 -> 73/68 _ 123c
14.5 -> 29/27 _ 124c
14.4 -> 72/67 _ 125c
14.2 -> 71/66 _ 126c
14.0 -> 14/13 _ 128c
13.8 -> 69/64 _ 130c
13.6 -> 68/63 _ 132c
13.5 -> 27/25 _ 133c
13.4 -> 67/62 _ 134c
13.2 -> 66/61 _ 136c
13.0 -> 13/12 _ 139c
12.8 -> 64/59 _ 141c
12.6 -> 63/58 _ 143c
12.5 -> 25/23 _ 144c
12.4 -> 62/57 _ 146c
12.2 -> 61/56 _ 148c
12.0 -> 12/11 _ 151c
11.8 -> 59/54 _ 153c
11.6 -> 58/53 _ 156c
11.5 -> 23/21 _ 157c
11.4 -> 57/52 _ 159c
11.2 -> 56/51 _ 162c
11.0 -> 11/10 _ 165c
10.8 -> 54/49 _ 168c
10.6 -> 53/48 _ 172c
10.5 -> 21/19 _ 173c
10.4 -> 52/47 _ 175c
10.2 -> 51/46 _ 179c
10.0 -> 10/9 _ 182c
9.9 -> 99/89 _ 184c
9.8 -> 49/44 _ 186c
9.7 -> 97/87 _ 188c
9.6 -> 48/43 _ 190c
9.5 -> 19/17 _ 193c
9.4 -> 47/42 _ 195c
9.3 -> 93/83 _ 197c
9.2 -> 46/41 _ 199c
9.1 -> 91/81 _ 202c
9.0 -> 9/8 _ 204c
8.9 -> 89/79 _ 206c
8.8 -> 44/39 _ 209c
8.7 -> 87/77 _ 211c
8.6 -> 43/38 _ 214c
8.5 -> 17/15 _ 217c
8.4 -> 42/37 _ 219c
8.3 -> 83/73 _ 222c
8.2 -> 41/36 _ 225c
8.1 -> 81/71 _ 228c
8.0 -> 8/7 _ 231c
7.9 -> 79/69 _ 234c
7.8 -> 39/34 _ 238c
7.7 -> 77/67 _ 241c
7.6 -> 38/33 _ 244c
7.5 -> 15/13 _ 248c
7.4 -> 37/32 _ 251c
7.3 -> 73/63 _ 255c
7.2 -> 36/31 _ 259c
7.1 -> 71/61 _ 263c
7.0 -> 7/6 _ 267c
6.9 -> 69/59 _ 271c
6.8 -> 34/29 _ 275c
6.7 -> 67/57 _ 280c
6.6 -> 33/28 _ 284c
6.5 -> 13/11 _ 289c
6.4 -> 32/27 _ 294c
6.3 -> 63/53 _ 299c
6.2 -> 31/26 _ 305c
6.1 -> 61/51 _ 310c
6.0 -> 6/5 _ 316c
5.9 -> 59/49 _ 322c
5.8 -> 29/24 _ 328c
5.7 -> 57/47 _ 334c
5.6 -> 28/23 _ 341c
5.5 -> 11/9 _ 347c
5.4 -> 27/22 _ 355c
5.3 -> 53/43 _ 362c
5.2 -> 26/21 _ 370c
5.1 -> 51/41 _ 378c
5.0 -> 5/4 _ 386c
4.9 -> 49/39 _ 395c
4.8 -> 24/19 _ 404c
4.7 -> 47/37 _ 414c
4.6 -> 23/18 _ 424c
4.5 -> 9/7 _ 435c
4.4 -> 22/17 _ 446c
4.3 -> 43/33 _ 458c
4.2 -> 21/16 _ 471c
4.1 -> 41/31 _ 484c
4.0 -> 4/3 _ 498c
3.9 -> 39/29 _ 513c
3.8 -> 19/14 _ 529c
3.7 -> 37/27 _ 545c
3.6 -> 18/13 _ 563c
3.5 -> 7/5 _ 583c
3.4 -> 17/12 _ 603c
3.3 -> 33/23 _ 625c
3.2 -> 16/11 _ 649c
3.1 -> 31/21 _ 674c
3.0 -> 3/2 _ 702c
2.9 -> 29/19 _ 732c
2.8 -> 14/9 _ 765c
2.7 -> 27/17 _ 801c
2.6 -> 13/8 _ 841c
2.5 -> 5/3 _ 884c
2.4 -> 12/7 _ 933c
2.3 -> 23/13 _ 988c
2.2 -> 11/6 _ 1049c
2.1 -> 21/11 _ 1119c
2.0 -> 2/1 _ 1200c

Now, there's no real reason to use decimal as string divisors. You could just as easily place a marker at 3.1 of a the string length as you could at 22/7 of the string length, but I wanted to see how this looked. I've also hidden any frequency ratios with numerators more than 99.

There are some conspicuous absences on this list. Like the justly tuned minor sixth, 8/5, or the justly tuned major seventh, 15/18, and the justly tuned minor seventh, 9/5. Our involution function certainly has less precision near the octave, so we might try using another decimal digit at the high end:

3.0 -> 3/2 _ 702c
2.96 -> 74/49 _ 714c
2.95 -> 59/39 _ 717c
2.92 -> 73/48 _ 726c
2.9 -> 29/19 _ 732c
2.88 -> 72/47 _ 738c
2.85 -> 57/37 _ 748c
2.84 -> 71/46 _ 751c
2.8 -> 14/9 _ 765c
2.76 -> 69/44 _ 779c
2.75 -> 11/7 _ 782c
2.72 -> 68/43 _ 793c
2.7 -> 27/17 _ 801c
2.68 -> 67/42 _ 809c
2.65 -> 53/33 _ 820c
2.64 -> 66/41 _ 824c
2.6 -> 13/8 _ 841c
2.56 -> 64/39 _ 858c
2.55 -> 51/31 _ 862c
2.52 -> 63/38 _ 875c
2.5 -> 5/3 _ 884c
2.48 -> 62/37 _ 894c
2.45 -> 49/29 _ 908c
2.44 -> 61/36 _ 913c
2.4 -> 12/7 _ 933c
2.36 -> 59/34 _ 954c
2.35 -> 47/27 _ 960c
2.32 -> 58/33 _ 976c
2.3 -> 23/13 _ 988c
2.28 -> 57/32 _ 999c
2.25 -> 9/5 _ 1018c
2.24 -> 56/31 _ 1024c
2.2 -> 11/6 _ 1049c
2.16 -> 54/29 _ 1076c
2.15 -> 43/23 _ 1083c
2.12 -> 53/28 _ 1105c
2.1 -> 21/11 _ 1119c
2.08 -> 52/27 _ 1135c
2.05 -> 41/21 _ 1158c
2.04 -> 51/26 _ 1166c
2.0 -> 2 _ 1200c

This got us our minor seventh, but not the other two chromatic 5-limit frequency ratios. It turns out those don't have finite decimal representations: A string divisor of 15/7 gives us a frequency ratio of 15/18, and a string divisor of 8/3 gives us a frequency ratio of 8/5.

I kind of like this? We've found a procedure which privileges a different set of ratios and intervals compared to normal just intonation.

It's not much of a difference: the 2.68 divisor gives us a frequency ratio of 67/42, which is a perceptually indistinguishable 5 cents flat of 8/5. The sounds are still there. But I still think it's a neat sound space. Maybe don't use the high precision divisors if you want a really distinct sound?

...