Overthinking the apocalypse

The notes in the Japanese folksong Sakura, Sakura, namely E F A B C, form a rather sombre scale (1-4-2-1-4) that's about as iconic as the song itself; to the point where both the song and the scale are downright stereotypes. Play anything in these notes and it sounds “Japanese”. But what is the scale called?

It's not this one either.

All over the Anglophone Internet, you'll see references to the “In” scale—”shadow scale”, as in one half of yin/yang (Japanese In/Yō)—as being the name of the Sakura scale. You will also see it variously refereed to as “Sakura scale”, “Miyako-bushi”, “Hirajōshi”, “Iwato”, “Kumoi”, or just “Japanese”. And you will spot mentions of something called “Insen” or “In sen” scale, which also shows as “Japanese scale”, and is alternately claimed to be the same thing as the Sakura scale—makes sense, since “In sen(pō)” is just “In mode”—or else something else entirely: 1-4-2-3-2. For example, scales-chords.com gives “Japanese scale (In sen)” in C as C Db F G Bb. Sakura transposed to C would use C Db F G Ab. This matters a lot; the Sakura scale has two intervals of a single semitone, which harmonically are dissonant, and give the scale its moody, melancholic atmosphere. The song Sakura adapted to the supposed “Insen” scale would be played with E F A B D; that just sounds off.

English Wikipedia also distinguishes “In scale” from “Insen” (Japanese for “In mode”), and claims the latter is a koto tuning by Yatsuhashi Kengyō that differs from Hirajōshi (=Sakura scale) by one note. It gives no sources for that except a vague link to a generic Japanese online dictionary (kotobank), which says the exact opposite: In-senpō (“shadow mode”) = In-onkai (“shadow scale”) = Hirajōshi (“plain tuning”). Also I'm pretty sure Kengyō predates the terminology “In”; and I could find no such tuning for koto either.

What gives?

Well here's a table I translated/adapted from the Japanese wikipedia:

Yō/Inaka-bushi ("light/country")	Ascending	C D F G Bb	2-3-2-3-2
	Descending	A G F D C	2-2-3-2-3
In/Miyako-bushi ("shadow/capital")	Ascending	C Db F G Bb	1-4-2-3-2
	Descending	Ab G F Db C	1-2-4-1-4

Mystery solved. The original classification of scales in yin/yang, “In” and Yō”, actually had two variants for each class. What is often called “In” in English, aka the Sakura scale proper, is the “In descending” (in reverse order; just read it descendingly in the table). And what is often called “In sen” is the “In ascending”.

Blessedly, that table was given with a citation: This analysis was from Meiji-period Uehara Rokushirō, Zokugaku Senritsu-kō. What he did was to classify the scales found in folk music as “yin/city” and “yang/country” styles, then correlate standard instrument tunings to Western music theory, and also proposing that the scales change a note when ascending.

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Personally I think Koizumi Fumio's tetrachord analysis (which focuses not on scales and octaves but the two nucleus tones and the colour-giving note between them) makes more sense as something that reflects the character of Japanese music, rather than trying to fit it into Western ways of thinking about music. I'm no musician or theorist but it just immediately struck me as accurate and useful; the tetrachords for ryūkyū or min'yō totally do sound like ryūkyūan or min'yō music, the tetrachord for miyakobushi captures the essence of songs like Sakura, and Koizumi's two nuclei feel much more natural to me than the notion of a “scale in the key of”—fooling around with the notes when playing Sakura on shinobue, I always felt like they dance around the gravitation of both E and A, rather than resolving into a “going home” to either of them. This is typical of J. folksongs in general.

I'm way out of my depth here but I don't immediately see the motivation for the “ascending” versions of the scales, and also I'm not sure where are these used. Are there folksongs using the “ascending” scales, or is this an artefact of Uehara's theory? Is it based on some sort of variant koto tuning or small deviations of canonical “scales” in practical contexts? (Koizumi's theory is more direct, like, “ok there are two nuclei separated by a perfect fourth, plus a third note between them that gives the melody its character, that's about it, all the other notes? oh they're just extras lol”)

In any case I think it's clear that the “In descending” is the one with most relevance. Japanese sources tend to prefer “Miyako-bushi” to refer to it. I also like “Sakura scale” in an English context because unlike all the “Insen” stuff it's unambiguous (it's the scale defined by the song) and evocative (everyone knows the song).

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What about the “Hirajōshi scale”? That's properly a koto tuning, as suggested by -jōshi (“tuning”). The modern version is, if you tune string 1 to D4, the others would go:

D4 - G3 - A3 - A3# - D4 - D4# - G4 - A4 - A4# - D5 - D5# - G5 - A5

D D# G A A# ; 1-4-2-1-4. Hirajōshi is the name of the koto tuning equivalent of the Miyakobushi scale. The same goes for “Iwato” and “Kumoi”, which are modes:

The names and exact intonation of each tuning will vary slightly depending on the ryūha (school style), but I've included here three well-known tunings. The most basic is Hira-jōshi [plain tuning], which uses the Miyako-bushi scale with strings 1 and 5 as they main note [key/tonic/prime]; then there's 雲居調子 Kumoi-jōshi ['in the clouds' tuning, 'distant' tuning; reference to a scene of longing in Genji?], which uses the Miyako-bushi scales with the main note on string 2, a fifth lower than Hira tuning; and finally Iwato-jōshi [“Iwato tuning”; a place name, the meaning of the reference is lost on me], with string 4 as the main, a fourth higher than Hira tuning. Changing the tuning merely transposes the melody; all of them are in the same Miyako-bushi scale.

This is credited to Hirano Kenji 1989, which I found in this exceptionally informative article by Mizusaki Masato. I still haven't fully sank my teeth into it, but the one silver lining about the confusion of “In” and “Insen scale” is that I found this text when trying to make sense of it. It's great.

So in a nutshell, “Hirajōshi”, “Iwato” and “Kumoi” all come from the same context, i.e. koto tunings based on the Miyakobushi/Sakura scale; and it's a random accident that the Anglosphere carried -jōshi (=“tuning”) for one of them but not the others. It should be noted that the koto originally didn't use the Miyakobushi or other folk scales, but rather the classical Ritsu scale from gagaku (court) music. Yatsuhashi Kengyō (1624-1645) is credited in bringing the miyakobushi scale as a koto tuning, seminally in the composition Rokudan-no-Shirabe. I do not know, however, that he is credited with inventing the “In mode scale (Japanese).”