MI: LIBRARY: THEORY: BASICS: ACCIDENTALS

Accidentals are symbols that indicate the raising or lowering of the pitch of a tone.  Accidentals are always placed in front of the note it affects.

A sharp () raises the pitch of a tone by a half step.  A flat () lowers the pitch of a tone by a half step.

A natural () is used to cancel a sharp or flat within a measure.

Except for the accidentals in the key signature, a bar line cancels all accidentals in a previous measure.

Except for the accidentals in the key signature, an accidental affects a note only in the measure in which it appears, and only that one line or space.  Exp.  the second note in this measure is F natural.

A double flat () lowers the pitch of a tone by two half steps (a whole step).
A double sharp () raises the pitch of a tone by two half steps (a whole step).

To cancel a double sharp or flat within a measure, use a double natural sign. ()

To cancel part of a double sharp or flat, use a combination of the natural sign and the sharp or flat signs.