artificial harmonic

To produce an artificial harmonic, a stringed instrument player (such as a guitarist) holds down a note on the neck with the left hand, thereby shortening the vibrational length of the string, uses a finger to lightly touch a point on the string that is an integer divisor of its vibrational length, and plucks or bows the side of the string that is closer to the bridge. This technique is used to produce harmonic tones that are otherwise inaccessible on the instrument. To guitar players, one variety of this technique is known as a pinch harmonic. Many guitarists, chiefly of the heavy metal genre (such as the guitarists in Slayer, Destruktur and Nile), also rapidly bend or use a vibrato on the string to create a high pitched squeal, in addition to creating the artificial harmonic.
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