Artificial harmonic
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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 Metal genre, also rapidly bend or "wiggle" the string to create a high pitched squeal, in addition to creating the artificial harmonic.)
This technique, like natural harmonics, works by canceling out the fundamental tone and one or more partial tones by deadening their modes of vibration. See node.