BazzLow
ENIT
Module 3 · Lesson 5

Accidentals and key signatures on the staff

Know how long an accidental lasts and what a key signature does on the staff.

Before this lesson: 3.4 Reading rhythm on the staff · 1.3 Sharps, flats and enharmonic notes

Lesson 1.3 introduced sharps, flats and naturals. Here is how they are written on the staff, and how long they last.

Accidentals

An accidental (♯, ♭, ♮, 𝄪, 𝄫) is written just before the note it changes. It applies to that note and to every later note on the same line or space until the end of the bar: the barline cancels it. Strictly it applies only in the same octave. Many editions add reminders anyway.

A courtesy (or cautionary) accidental, sometimes in brackets, is a reminder in the next bar. It is not required, but it is helpful.

Bass clef staffOne bar. First note: F♯, with the sharp written. Second note: another F on the same line, so it is still F♯. Third note: an F in a different octave, so it is a plain F. Fourth note: a natural sign cancels the sharp, so it is F.♯♮F♯F♯FF
One bar. First note: F♯, with the sharp written. Second note: another F on the same line, so it is still F♯. Third note: an F in a different octave, so it is a plain F. Fourth note: a natural sign cancels the sharp, so it is F.

Key signatures

A key signature is a group of sharps or flats written right after the clef, on every line of music. It applies to every note with that letter name, in every octave, for the whole piece, until a new key signature appears. A key signature never mixes sharps and flats.

Example: one sharp on the F line means every F is played F♯, unless an accidental says otherwise.

Bass clef staffA key signature of one sharp on the F line. Both Fs in the bar, in different octaves, are F♯; G and A are natural.♯44F♯GAF♯
A key signature of one sharp on the F line. Both Fs in the bar, in different octaves, are F♯; G and A are natural.

Which key signatures exist, their order and which key each one means are explained in Module 5.

Try it

Read both diagrams and say each note name before playing it. Then play them.

New terms