artificial harmonic

An "artificial" harmonic is distinguished from a "true" harmonic only in the method by which it is performed. Typically artificial harmonics are played on an electric guitar because they are typically high order harmonics which would be nearly inaudible without the huge amounts of gain a typical guitar amp can deliver, though they may be performed on any stringed instrument that you can manage to play with a plectrum.

To play an artificial harmonic, hold your guitar pick between your thumb and index finger as you normally would, except allow only a tiny amount of the pick to protrude past the flesh on the side of your thumb. When you strike a string, immediately after, nearly simultaneously, you want the edge of your thumb to strike the string as well. The idea is, you want your thumb to very briefly mute the string as you play it right at a node so that the string is stopped from vibrating except at harmonics which naturally have a node where your thumb has hit it. (It sounds more difficult than it actually is, it's really quite easy once you get the knack.) So, the location on the string where you pluck it is important. There are typically some nice ones to be found by plucking near the neck pickup. To find them, you can rapidly pluck the string in the manner described above while moving your plucking hand slowly from the bridge towards the neck. As you pass over various nodes, you will hear different harmonics.

In contrast, "true" harmonics, or just "harmonics" are performed by damping the (usually unfretted) string at node points with the fretting hand. Artificial harmonics are easier to play when the strings are fretted, since the fretting hand is not involved in the production of the harmonic.

In the classical guitar world, artificial harmonic usually refers to a low-order harmonic (i.e. one in which the frequency produced is a low integer multiple of the 'base' note, most often a simple octave) which is performed on a fretted string.

Assuming you're playing 'right-handed' (reverse the instructions if not) the left hand frets the string, and the index finger of the right hand is placed gently on the string at the appropriate place, while the right-hand thumb plucks (though it can be plucked with the another finger, usually the third, if a simultaneous bass note is required).

The plucking should usually be done on the side of the harmonic 'node' (where the finger rests) which is nearest the bridge, in order to maximise the volume of the note produced; though, as the string is all vibrating at the same frequency (just as it does in a 'normal' harmonic) the pitch would be unaffected by plucking on the 'wrong' side.

For example, fingering the 3rd fret on the top E string with the left hand, resting the index finger of the right hand on the same string just above the 15th fret, and plucking with the thumb, gives a G exactly one octave above the G that would be obtained by plucking the string without the harmonic.

On a classical guitar, this can give a delicate 'musical toy' effect, as, for example, in Agustin Barrios Mangore's piece El sueno de la Munequita (The sleep of the Little Doll).

Another way of achieving artificial harmonics on a guitar is through tapping. The technique is similar to both standard tapping and the classical technique described above.

Finger a note with your fretting hand (left hand for righties). Then tap the string quickly with your playing hand an appropriate distance from the fretted note (12 (octave), 7 (octave + fifth), 5 (two octaves), or 9 (two octaves + fourth) frets away are good (see harmonic), ranked easiest to hardest for sounding purposes), right over the fretwire of the appropriate fret. For example, to tap the octave harmonic for the third fret of the A string, you would tap quickly on the A string over thefretwire between the 15th and 16th frets.

This technique should be performed quickly; what you're trying to do is bounce the string off of the fret so that the harmonic sounds, not hold it down so that that fret's note sounds.

This gives a sharper sound than touching the harmonic would.

This can also be performed with a pick by tapping with the edge of the pick in the right place. This may be easier, since the edge of the pick is smaller and can be more accurate.

On a side note: the technique that ferrouslepidoptera describes is also referred to as "pinch harmonics" because of the way the note is sounded: the thumb pinches off the note at the appropriate node.

For a modern example of this, listen to Van Halen's instrumental "316"; Eddie Van Halen finishes off the piece by tapping an arpeggio.

Another advantage of the artificial harmonic is that it can be bent; node the harmonic point and then bend the string with your fretting hand for some interesting results.

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Another way of fingering the harmonic is by using the opposite hand configuration that JK mentions: holding the fingers as if one was holding a pick, touching the string with the playing thumb, and playing the harmonic with the index finger immediately behind the thumb.

Harmonic techniques are not limited to the guitar. In fact, classical string instruments are capable of producing these harmonics. To play a harmonic, instead of fingering a note as usual, the performer lightly touches the string with a finger. This causes a high-order harmonic to resonate throughout the string at twice the normal frequency, producing a ghostly tone. An excellent example of the effects that can be achieved may be found in the final movement of Beethoven's string quartet op. 130.