Harmonics are high sounding overtones singled out from the harmonic range.

Natural Harmonics

Natural harmonics are the singling out of one overtone from the harmonic range. A normal note may sound like a single note but it is really a combination of many overtones. These overtones may be singled out by lightly touching the string at certain points with the left hand.

Many players use harmonics for tuning their bass. Playing a harmonic on the 5th fret of the E string will produce the same note as the harmonic on the 7th fret on the A string and so on for each string. The difference between the two strings is more noticable when using harmonics so tuning this way provides greater accuracy.

The strongest harmonics are found on the twelfth fret. Touching lightly above the twelfth fret will cause the string to vibrate in two halves which produces a note one octave higher than the open string. Touching lightly above the fifth fret will cause the string to vibrate in four quarters which produces a note two octaves higher than the open string. See the section on the names of the harmonic notes for other notes.Harmonics are played as follows:

• Place your finger(s) above the desired note(s).

• Touch the string(s) lightly without pushing down to the fingerboard.

• Play the note(s) using you preferred right hand technique (free-stroke is best for playing harmonic chords).

• Your left hand finger(s) can be lifted off the strings after you've played the notes. In this video I'm able to play new notes over the previous ones as they can all ring without any further contact with the left hand.

You sometimes see a written instruction to play harmonics without any special notation. Another method is to use a diamond shaped note head where you place your fingers. Notice that the following two notes are of identical pitch. i.e. A above the stave.

Artificial Harmonics

An artificial harmonic is a right hand technique which involves touching the string with one finger or your thumb and using another finger or a pick to pluck the same string. The advantage of this is that you can turn any note into a harmonic. A well known example of this technique is Weather Report’s "Birdland" where Jaco Pastorius plays what sounds like a guitar line.

The following example demonstrates how these artificial harmonics are like pinching the string between the finger and thumb. Heavy metal guitarists use this technique with distortion to produce squeals.

Harmonic Slides

On a fretless bass you can play a harmonic and then slide this note either up or down the neck. The slide is from pushing your finger onto the fingerboard after playing the harmonic and then maintaining pressure on the fingerboard during the slide.