**Accidentals** are symbols used to alter the [[pitch]] of a note. The black keys of the [[piano keyboard]] are named using the letter names of the adjacent white keys, either a half step above or below, with the addition of an accidental. ## Sharps and Flats A **sharp (♯)** raises a note by a half step, whereas a **flat (♭)** lowers a note by a half step. In **Example 1** below, the G has been raised by a half step to G♯ (G-sharp), while the A has been lowered by a half step to A♭ (A-flat). Both of these notes correspond to the same pitch or black key on the piano keyboard. The relationship between two notes that have the same pitch but are spelled differently—such as G♯ and A♭—is known as [[enharmonic equivalence]]. The notes themselves are said to be **enharmonically equivalent**. **Example 1.** Treble clef staff with piano keyboard. ![[accidentals example 1.png]] > [!NOTE] Important! > It is important to note that, while we say or write accidentals *after* the note name (e.g., “D-flat” or “E-flat”), they are placed *before* the note on the staff. Accidentals apply to all subsequent notes in the same measure that are on the same line or space. In the first measure of **Example 2** below, all four notes are E♭, but we only need to write the accidental the first time it is used. Likewise, in the second measure, the accidental applies to both the first and last notes of the measure. **Example 2.** Treble clef staff showing that accidentals carry through the measure. ![[accidentals example 2.png]] ## The Black Keys Now that we’ve discussed sharps and flats, we can label the rest of the black keys on the keyboard. **Example 2** shows one octave of the piano keyboard with the white and black keys labeled. **Example 2.** Piano keyboard with white and black keys labeled. ![[accidentals example 3.png]] ## Naturals A **natural (♮)** cancels the effect of any preceding accidentals, returning a note to its original letter name and white-key position on the keyboard. In **Example 4** below, the first and second notes are both F♯ whereas the third and fourth notes are both F. **Example 4.** Treble clef staff showing sharps and naturals. ![[accidentals example 4.png]] ## Double Sharps and Double Flats As its name suggests, a **double sharp (𝄪)** raises a pitch by two half steps (or whole step). Likewise, a **double flat (𝄫)** lowers a pitch by two half steps (or whole step). ## Courtesy Accidentals A **courtesy accidental** is an accidental that is technically not required but given for clarity. In **Example 5** below, both measures are played exactly the same. Although a natural sign is not strictly necessary for the fourth note in the second measure, a courtesy accidental reassures the performer that the E♮ is intentional and not an error. **Example 5.** Treble clef staff demonstrating the use of a courtesy accidental. ![[accidentals example 5.png]] ## Summary The table below lists the five standard accidentals used in Western music and their effects. | Symbol | Name | Effect | | ------ | ------------ | ----------------------------- | | 𝄪 | double sharp | raises a note by a whole step | | ♯ | sharp | raises a note by a half step | | ♮ | natural | cancels a previous accidental | | ♭ | flat | lowers a note by a half step | | 𝄫 | double flat | lowers a note by a whole step | Using standard accidentals, any line or space on the staff may represent one of five possible pitches. **Example 6** below shows the possibilities for the second line of the treble clef: G𝄫, G♭, G♮, G♯, and G𝄪. Moving from left to right, the notes are arranged sounding lowest to highest. ![[accidentals example 6.png]]