Tones and Semitones
A semitone is the smallest distance between two notes used in western music. On the guitar, notes which are a semitone apart are one fret apart, (e.g., the note C on the 3rd fret 5th string is one semitone above the note B at the second fret).
This could also be reversed, i.e., the note B is one semitone (one fret) below the note C. Notes which are a tone (two semitones) apart, are two frets apart. An example of this would be the notes F and G on the sixth string or the first string, or the notes G (open) and A (2nd fret) on the third string.
Sharps
A sharp sign ( # ), placed before a note, raises the pitch of that note by one semitone (one fret). To play a sharp note picture the normal note (the natural note) on the fretboard and then place your next finger on the next fret. Try these examples:
Using sharps you can now play five new notes, which occur between the seven natural notes you already know. The following exercise uses all twelve notes which occur within one octave of music. Note that there are no sharps between B and C, or E and F.
This is because they are already one semitone apart and there is no room for an extra note between them. Play the following exercise slowly and steadily, making sure you use the correct fingering.
The exercise you have just played is a chromatic scale. Chromatic scales consist entirely of semitones (i.e., they move up or down one fret at a time) and the start and finish notes are always the same (this is called the key note or tonic). The chromatic scale can be built on any note.
Here is the D chromatic scale:
The Natural Sign
This is a natural sign.
A natural sign cancels the effect of a sharp or flat for the rest of that bar, or until another sharp or flat sign occurs within that bar.
A sharpened note stays sharp until either a bar line or a natural sign ( @ ) cancels it as in the following example;
Now play this exercise which makes use of both sharp and natural signs. Play it slowly at first and say the name of each note out loud as you play it.
To improve your knowledge of sharps and natural signs, find each of the following notes on the fretboard of your guitar. On a sheet of paper, write down each note including its name above or below it.
Flats
A flat ( b ) does the opposite of a sharp. Placed immediately before a note, it lowers the pitch of that note by one semitone.
When an open string note is flattened, the new note must be located on the next lower string.
The use of sharps and flats means that the same note can have two different names. For example, F# = Gb and G# = Ab. These are referred to as enharmonic notes. The following diagram outlines all of the notes in the first position on the guitar (including both names for the enharmonic notes). The first position consists of the open string notes and the notes on the first four frets.
The following example demonstrates two octaves of the E chromatic scale. Notice that sharps are used when the scale ascends and flats are used as it descends. This is common practice when writing chromatic passages in music.
As with sharps, flats are cancelled by a bar line or by a natural sign.
Here is an exercise to improve your knowledge of flats. Once again, using a sheet of paper, write down each note including its name above or below it.
