Editing Accidental (music) (section)

==Microtonal notation==
<!-- I have better images for the symbols uploaded but I don't know how to add them to this page or link the different PNG sizes together form an expandable svg files -->
{{Image frame|content=<score> {
\override Score.TimeSignature
#'stencil = ##f
    \relative c'' {
        \time 4/4
        aeh2 aeseh
        aih aisih
    }  }
</score>|width=220|caption=A common notation for quarter tones. From left to right, half-flat, flat-and-a-half, half-sharp, sharp-and-a-half.}}
Composers of [[microtonal music]] have developed a number of notations for indicating the various pitches outside of standard notation. One such system for notating [[quarter tone]]s, used by the Czech [[Alois Hába]] and other composers, is shown.

In the 19th and early 20th centuries, when Turkish musicians switched from their traditional notation systems—which were not staff-based—to the European staff-based system, they refined the European accidental system so they could notate Turkish scales that use intervals smaller than a tempered semitone. There are several such systems, which vary as to how they divide the octave they presuppose or the graphical shape of the accidentals. The most widely used system (created by [[Rauf Yekta Bey]]) uses a system of four sharps (roughly +25 [[cent (music)|cent]]s, +75 cents, +125 cents and +175 cents) and four flats (roughly −25 cents, −75 cents, −125 cents and −175 cents){{citation needed|date=March 2019}}, none of which correspond to the tempered sharp and flat. They presuppose a Pythagorean division of the octave taking the [[Pythagorean comma]] (about an eighth of the tempered tone, actually closer to 24 cents, defined as the difference between seven octaves and 12 just-intonation fifths) as the basic interval. The Turkish systems have also been adopted by some Arab musicians.

[[Ben Johnston (composer)|Ben Johnston]] created a system of [[Musical Notation|notation]] for pieces in [[just intonation]] where the unmarked C, F, and G major chords are just major chords (4:5:6) and accidentals create just tuning in other keys. Between 2000 and 2003, Wolfgang von Schweinitz and [[Marc Sabat]] developed the Extended Helmholtz-Ellis Just Intonation (JI) pitch notation, a modern adaptation and extension of the notation principles first used by [[Hermann von Helmholtz]], [[Arthur von Oettingen]], and [[Alexander John Ellis]] that some other musicians use for notating extended just intonation.<ref>{{Cite book|url=https://books.google.com/books?id=OnN_DwAAQBAJ&q=musicians+use+for+notating+extended+just+intonation+ellis&pg=PA83|title=Being Time: Case Studies in Musical Temporality|last1=Glover|first1=Richard|last2=Harrison|first2=Bryn|last3=Gottschalk|first3=Jennie|date=2018-12-27|publisher=Bloomsbury Publishing USA|isbn=978-1-62892-272-1|language=en}}</ref>