# Alterations in 24-EDO

The following table shows the alterations in the 24-tone equal-temperament system (24-EDO, quarter-tone system) up to the five-quarters-tone.

- go – Gould Notation
- 5 × 2 combined arrow symbols after Gould (U+E270 - U+E279) for quarters-tones, and standard sharp / flat symbols (U+E260 - U+E264).
- stz – Stein / Zimmermann Notation
- Fractional sharp symbols and quarter-tone flat symbol after Richard Stein
(U+E282 - U+E284)
and three-quarters-tone flat symbol after Bernd A. Zimmerman (U+E285)
(replacing Stein's “sesquiflat” symbol)
for quarter-tones,
and standard sharp / flat symbols (U+E260 - U+E264).
Also known as Tartini / Couper notation.

Note: The notation uses the narrow shape of the reversed flat (U+E284, U+E285). - stc – Stein / Couper Notation
- Variant of stz with the three-quarters-tone flat symbol after Mildred Couper (U+E489) (merger of mirrored flat symbols).
- stvt – Stein / Van Blankenburg / Tartini Notation
- Fractional sharp symbols after Richard Stein (U+E282, U+E283), quarter-tone flat symbol after Van Blankenburg (U+E488) (also known as “Tartini's hook”), three-quarters-tone flat symbol after Giuseppe Tartini (U+E487), and standard sharp / flat symbols (U+E260 - U+E264).
- arrow – Arrow Notation
- Arrow after Gould (U+E27A, U+E27B) for quarter-tones, and standard sharp / flat symbols (U+E260 - U+E264). All symbols are placed either alone or a standard symbol is combined with an arrow.
- sag – Sagittal Notation
- 4 × 2 Spartan Sagittal single-shaft and multi-shaft symbols after George D. Secor and David C. Keenan (U+E30A ... U+E335). This is the "Pure Sagittal notation" in contrast to msag. It uses one distinct symbol for each degree up to the whole tone. For the five-quarters-tone degree, two symbols are combined.
- msag – Mixed Sagittal Notation
- 1 × 2 Spartan Sagittal single-shaft symbols (U+E30A, U+E30B) for quarter-tones, standard sharp / flat symbols (U+E260 - U+E262, U+E264), and large double-sharp symbol (U+E47D). They are placed like arrow.
- arabic – Arabic Notation
- 4 × 2 Arabic symbols (U+ED30 - U+ED38).
This notation uses its own natural sign (U+ED34 instead of U+E261).
See
`"arabic.ly"`

in LilyPond for Arabic maqamat etc., which also uses a different three-quarters-tone flat symbol. - persian – Persian Notation
- Persian symbols Koron and Sori after Ali-Naghi Vaziri (probably) (U+E460, U+E461) for quarter-tones, and standard sharp / flat symbols (U+E260 - U+E264). They are placed like arrow. See Persian music notation by Kees van den Doel for proper Persian microtonal alterations, note names, keys, etc.
- four – Digit 4 Notation
- sharp / flat symbols with digit 4 (U+E47E, U+E47F) for quarter-tones, and standard sharp / flat symbols (U+E260 - U+E264). They are placed like arrow.
- fern – Ferneyhough notation
- 2 combined digit-4-arrow symbols after Brian Ferneyhough (U+E48E, U+E48F) for quarter-tones, and standard sharp / flat symbols (U+E260 - U+E264).
- haba – Hába Notation
- 6 combined symbols after Alois Hába (U+EE64 - U+EE69) for quarter-tones, and standard sharp / flat symbols (U+E260 - U+E264).

- ↑abcdIn most of the notation styles like
go, stz and
arrow, the one-quarter-tone and
three-quarters-tone degrees have two distinct, enharmonically equivalent
accidentals.
Therefore, Ekmelily defines two note name suffixes each, e.g.
`qs`

and`saqf`

(English) or`ih`

and`iseh`

(German). However, LilyPond does not support different accidentals for the same alteration. As a provisional solution, the combined note names (e.g.`-saqf`

or`-iseh`

) have slightly differing alterations and are therefore not suitable for transposition and MIDI output.