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Accidental position and effect

Unlike the key signature, an accidental is placed within a measure, just before the altered note. Its effect stops at the end of the measure in which it is placed.

Accidental position

An accidental is placed immediately before the altered note, at the same height (on the same staff line or space).

FIGURE 1 - Examples of accidentals
Natural G G sharp Natural G G flat

Be careful to align well the accidental with the note. Accidental must always precede the note it alters (Figures 2 and 3)

FIGURE 2 - Correct position of an E flat and counterexamples
Correct position Wrong positions

FIGURE 3 - Correct position of an F sharp and counterexamples
Correct position Wrong positions

Accidental effect

Accidental only has effect for the note(s) that follow it on the same line or the same space, until the end of the bar (or measure) in which it is placed.

FIGURE 4 - Effect of accidental. In orange, the notes are flat. In green, the notes are natural.
E All Es that followare flat, untilthe bar line. The bar line cancels the effect of allthe accidentals that are in the previous bar. These Es arenatural

To cancel the effect of an accidental within a measure, it is necessary to place a natural () in front of the note in order to restore its natural state.

FIGURE 5 - Effect of the natural. In orange, the notes are sharps. In green, the notes are natural.
The natural cancels the sharpfound at the begining of the bar

Be careful to identify the accidentals located at the beginning of the measure. A common mistake for beginners is to forget the presence of a sharp or a flat and play a natural note at the end of the measure while it should be altered.

Cautionary or courtesy accidentals

As musicians are sometimes distrated, they occasionally fail to think of canceling the effect of an accidental once the bar is over. By tradition, it is therefore common to encounter so-called "courtesy" or "cautionary" accidentals, to remind the musician that a previously altered note becomes natural for example. A cautionary accidental is therefore not essential according to the traditional rules of writing music, but facilitates the sight reading of a musician, thus avoiding many errors and saving valuable time.

FIGURE 6 - A courtesy natural is added in front of the first E of the second measure to avoid any confusion with the many E present in the previous measure.

FIGURE 7 - Variant of the previous example with sharps.

Last update on 2021/05/07

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