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Lesson 9: Sharps, flats and naturals

Often in notated music, you'll come across sharp, flat and natural signs placed in front of notes. These accidentals, as they are called, indicate that the pitch of the note is to be raised (sharped or sharpened) or lowered (flatted or flattened) by a semitone or half step. To restore a note previously altered by a sharp or flat back to its original pitch, the natural sign is used.

Fig 9-1: The Accidentals (sharp, flat and natural)

As a semitone is equal to exactly one fret on the guitar, the simplest way to alter any inflected note is by raising or lowering the pitch by one fret. In the example above, the note A is played on string 3 fret 2, so A# (A sharp) is played on string 3 fret 3. and Ab (A flat) is played on string 3 fret1.

Flatted open string notes

Open strings present a slight problem here, though, as they can't be lowered any further. The solution is to locate the same note on a lower string and lower that by one fret:

Fig 9-2: Flatted open string notes

Effects of accidentals.
An accidental affects not only the note it's placed in front of. It also affects all other notes of that pitch within the same bar or measure, unless another accidental cancels it:

Fig 9-3 The effects of accidentals

Reading Exercise 9

This is the melody to Bourree by JS Bach, originally written for lute.

Listen

Further Practice
Use the 'pitch trainer' tool at the end of these lessons for more practice in naming and playing all the notes you've learned so far. Select level 2 (Bass and mid-range) and "include sharps and flats".