Accidentals:

What are accidentals?:

So far we have looked at how we read 'natural notes' e.g. A,B,C etc. On a keyboard these are shown by the white keys. Between these notes we have black keys which are represented by accidentals. Accidentals are used to raise and lower the pitch of the note by a semitone. They are symbols placed just before the note so that a musician can easily read it ahead of playing the note.

An intro to tones and semitones:

Tone: A tone is the equivalent to moving up or down two keys on the piano. For example if we start on C and move up a tone we land on the note D as we jump from C to C sharp and to D.

Semitone: A semitone is (as the name suggests) half a tone. So we move up or down by one key. So if we start on F and move up a semitone we end up on F sharp.

Accidentals come in two forms. Sharp and flat. A sharp raises the note by a semitone and a flat lowers the note by a semitone. An accidental can be both a sharp and a flat depending on the key signature (see Unit 1 Lesson 9). For example the note G sharp is also A flat as it is in between the notes G and A on the keyboard.

You can also get double sharps and flats which is the equivalent of changing the pitch by a tone. However these aren't very common in modern music.

The other important rule with accidentals is that once an accidental is written all of the same notes become accidentals until it is canceled by the use of a natural sign (see top left picture).

Example:

Here is a short recording of a chromatic scale starting on C. A chromatic scale used all of the notes on the key board so it is a perfect example of showing how accidentals sound. You will notice that a B sharp sounds the same as a C and that a C flat is the same as B. This is because when looking at a keyboard you will notice that there are no black keys separating the notes C and B and also E and F. This means that if a musician saw a B sharp written down in the music they would play a C.

Accidentals.mov

Why do we need accidentals?:

Accidentals are used to help reduce the number of notes a musician has to remember and condense the number of notes that appear on the stave. Accidentals play essential part in adding depth and expression to music. For example by changing the third of a chord by a semitone a musician can completly change the sound of the chord (see Unit 1 Lesson 8).