What is a harmonic on violin?

In string music, a harmonic (often called a "natural harmonic" or "flageolet") is a sound produced when a string is lightly touched at a specific point, rather than pressed all the way down as in normal playing. This results in a higher-pitched sound that resonates sympathetically with the string's natural resonant frequencies. Harmonics are often used to create a bell-like or ethereal effect in violin music.

To play a harmonic, the player lightly touches the string with the side of the fingernail, at one of the specific harmonic nodes of the string. These nodes are located at specific fractions of the string's length, and are determined by the laws of physics and the tension of the string. When touched at these points, the string vibrates in a different mode, producing a higher-pitched sound than when played normally.

Harmonics can be produced at various points along the string, each resulting in a different pitch. The most common harmonics are the octave, the fifth, the fourth, the major third, and the minor third. These harmonics are produced by touching the string at 1/2, 1/3, 1/4, 1/5, and 1/6 of its length, respectively.

Harmonics can be played on any string instrument, but they are particularly common in violin music. Violinists often use harmonics to create a wide range of expressive effects, from delicate shimmering tones to soaring melodies.