Foundations reference
Accidentals
An accidental is a notation symbol that modifies the expected pitch of a written note. Accidentals help music represent pitches outside a key signature and spell musical relationships clearly.
Developing reference
Overview
Sharps raise a written note and flats lower it, while a natural sign cancels an alteration that would otherwise apply. Double sharps and double flats extend the same principle when a musical context requires them.
An accidental changes the written pitch associated with a letter name. Its precise duration in notation depends on the notational convention and measure context.
Musical Spelling
Accidentals do more than identify a sounding pitch. They preserve scale-degree and chord-tone relationships, so two notes that sound alike in equal temperament may still require different written names.
Key and Local Context
A key signature establishes a recurring set of sharps or flats. Local accidentals then alter particular notes when a melody or harmony moves beyond that collection or needs a more precise spelling.
Applications
Understanding accidentals supports accurate reading, scale construction, chord analysis, transcription, and communication. It also prevents enharmonically equivalent pitches from being treated as interchangeable in every theoretical context.