Add arrow heads as accidentals.

[Ra-Yo-Su]

Several microtonal notation systems use arrow heads (looking like ∧, ∨, >, <) as accidentals. These include:

• Up/Down notation, which is more or less the standard notation in 22EDO and 31EDO, but also used elsewhere. Lacking ∧ and v ("up" and "down") users often resort to other symbols, however.
• Porcupine notation, which also uses ^ and v.
• Helmholtz/Ellis/Wolf/Monzo (HEWM) notation, which uses all four arrow heads (hence, including "more" and "less" in addition to "up" and "down") as well a many other symbols.

The addition of "up" and "down" (^ and ∨) accidentals to SMuFL is sorely needed, but it seems silly to not add right/more and left/less (> and <) at the same time. Given that the latter two don't have standardized names, I propose to call those "more" and "less", respectively. (See also below.)

Neither size and shape of these symbols is standardized (because users have to resort to various tricks to get anything resembling them), but in all cases they are intended to have the same size as a note head.

These accidentals are used on their own and in combination with other accidentals.

I'm not sure where exactly these four new accidentals should be added, but "Other accidentals" seems the most obvious location.

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details

To be added to "Other accidentals".

symbols:
∧
∨
>
<

• All the same size as note heads, and aligned with note heads. All four should be the same symbol, but rotated.
• The Up and Down accidentals tend to be less sharp (i.e. have slightly less sharp angles) than the arrow heads that are already available as "symbols" (not as accidentals). They look more like logic symbols ∧ (and) and ∨ (or) than like the available arrow heads.
• Accidentals are used on their own or in front of another accidental. (Including in front of the same. 22EDO Porcupine notation uses ∧∧ and ∨∨ accidentals, for example.)

names:
accidental up
accidental down
accidental more
accidental less

• I suppose it might be useful to add some further identifier after "accidental", but I'm not sure what that identifier should be as these symbols are used in several notations. The most important for the first two is Up/Down notation, but "accidental up down up" sounds like a very bad idea.

pitch offset values:
All four have slightly different functions depending in which notation they are used for.
∧ : one degree up (e.g. 54.5c in 22EDO, 38.7c in 31EDO, etc.) or 33/32 up (53.3c).
∨ : idem, but down.
> : 64/63 up (27.3c) or notation-specific small upwards offset.
< : idem, but down.

• As mentioned before, the first two are used by far the most, and have – for that reason – more determinate values.

[wpcopper]

Attached please find the symbols used in intonalism for this purpose.   Indeed, it is the up and down arrows (I call them neutral accidentals) that are most urgently needed, since most other microtonal systems do not offer them. William Copper If the attachment fails to be delivered, you may find the png image here: https://williamcopper.com/intonation_symbols.png

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On 6/8/2020 6:30 AM, Ra-Yo-Su wrote: Up/Down notation is one of the most common microtonal notation systems. It uses sharps, flats, and naturals with arrows. The latter are not ideal, however, partially because they make a score look overly busy, and partially because they are too easily confused with sharps with arrows if you can only keep one eye on the score. For that reason, simple up and down arrow heads ^ and v that align with the note heads (and that are roughly the same size or slightly smaller than note heads) are often preferred. (And, as far as I know, these were also the symbols intended by the original authors of Up/Down notation.) Something like (or slightly smaller than) the image below: updopwnpos <https://user-images.githubusercontent.com/66622393/84025589-cf9ccd00-a9c6-11ea-864c-5400be0c0e62.png> — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#124>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AENNCHSSMTYIPTJGJB3AFUTRVTDWZANCNFSM4NYKEZTQ>.

[dspreadbury]

@wpcopper, it looks to me like you are talking about something completely different, which is already encoded in SMuFL, under the name Gould arrow quartertone accidentals (24-EDO).