Audio: accidental (0:05)
accidental plays a melody on a flute. The accidental figure shows two different notations:
An accidental is a symbol in a score that modifies the pitch of a note:
The effect of a sharp or flat lasts for a single bar only and affects all notes of a similar pitch that follow in that bar. When the bar ends the sharpened or flattened note reverts back to its normal pitch. A natural is used to cancel the effect of a sharp or flat within a bar.
The effect of a key signature lasts to the end of a piece of music or until the next key signature change.
Modulation in music is signalled in a score with an accidental or a change in key signature or both together. An accidental is usually indicative of short-term modulation, a change of key signature is usually a sign of long-term modulation.