Playing a string harmonic (a flageolet) is a
string instrument
String instruments, stringed instruments, or chordophones are musical instruments that produce sound from vibrating strings when a performer plays or sounds the strings in some manner.
Musicians play some string instruments by plucking the ...
technique
Technique or techniques may refer to:
Music
* The Techniques, a Jamaican rocksteady vocal group of the 1960s
*Technique (band), a British female synth pop band in the 1990s
* ''Technique'' (album), by New Order, 1989
* ''Techniques'' (album), by M ...
that uses the
nodes
In general, a node is a localized swelling (a "knot") or a point of intersection (a Vertex (graph theory), vertex).
Node may refer to:
In mathematics
*Vertex (graph theory), a vertex in a mathematical graph
*Vertex (geometry), a point where two ...
of natural
harmonic
A harmonic is a wave with a frequency that is a positive integer multiple of the ''fundamental frequency'', the frequency of the original periodic signal, such as a sinusoidal wave. The original signal is also called the ''1st harmonic'', the ...
s of a musical
string
String or strings may refer to:
*String (structure), a long flexible structure made from threads twisted together, which is used to tie, bind, or hang other objects
Arts, entertainment, and media Films
* ''Strings'' (1991 film), a Canadian anim ...
to isolate
overtones. Playing string harmonics produces high pitched tones, often compared in timbre to a whistle or flute. Overtones can be isolated "by lightly touching the string with the finger instead of pressing it down" against the
fingerboard
The fingerboard (also known as a fretboard on fretted instruments) is an important component of most stringed instruments. It is a thin, long strip of material, usually wood, that is laminated to the front of the neck of an instrument. The stri ...
(without
stopping). For some instruments this is a fundamental technique, such as the Chinese
guqin
The ''guqin'' (; ) is a plucked seven-string Chinese musical instrument. It has been played since ancient times, and has traditionally been favoured by scholars and literati as an instrument of great subtlety and refinement, as highlighted b ...
, where it is known as ''fan yin'' (
泛音, lit. "floating sound"), and the Vietnamese
đà n bầu.
Overtones
When a
string
String or strings may refer to:
*String (structure), a long flexible structure made from threads twisted together, which is used to tie, bind, or hang other objects
Arts, entertainment, and media Films
* ''Strings'' (1991 film), a Canadian anim ...
is plucked or bowed normally, the ear hears the
fundamental frequency
The fundamental frequency, often referred to simply as the ''fundamental'', is defined as the lowest frequency of a periodic waveform. In music, the fundamental is the musical pitch of a note that is perceived as the lowest partial present. In ...
most prominently, but the overall sound is also colored by the presence of various
overtones (frequencies greater than the fundamental frequency). The fundamental frequency and its overtones are perceived by the listener as a single note; however, different combinations of overtones give rise to noticeably different overall tones (see
timbre). A harmonic overtone has evenly spaced nodes along the string, where the string does not move from its resting position.
Nodes
The nodes of natural harmonics are located at the following points along the string:
Above, the length fraction is the point, with respect to the length of the whole string, the string is lightly touched. It is expressed as a fraction , where ''m'' is the mode (2 through 16 are given above), and ''n'' the node number. The node number for a given mode can be any integer from 1 to . However, certain nodes of higher harmonics are coincident with nodes of lower harmonics, and the lower sounds overpower the higher ones. For example, mode number 4 can be fingered at nodes 1 and 3; it will occur at node 2 but will not be heard over the stronger first harmonic. Ineffective nodes to finger are not listed above.
The fret number, which shows the position of the node in terms of half tones (or frets on a fretted instrument) then is given by:
:
With ''s'' equal to the
twelfth root of two
The twelfth root of two or \sqrt 2/math> (or equivalently 2^) is an algebraic irrational number, approximately equal to 1.0594631. It is most important in Western music theory, where it represents the frequency ratio ( musical interval) of a se ...
, notated ''s'' because it's the first letter of the word "semitone".
Artificial harmonics
![Artificial_harmonic](https://upload.wikimedia.org/wikipedia/commons/b/b3/Artificial_harmonic.png)
When a string is only lightly pressed by one finger (that is, isolating overtones of the open string), the resulting harmonics are called natural harmonics. However, when a string is held down on the neck in addition to being lightly pressed on a node, the resulting harmonics are called artificial harmonics. In this case, as the total length of the string is shortened, the fundamental frequency is raised, and the positions of the nodes shift accordingly (that is, by the same number of frets), thereby raising the frequency of the overtone by the same interval as the fundamental frequency.
Artificial harmonics are more difficult to play than natural harmonics, but they are not limited to the overtone series of the open strings, meaning they have much greater flexibility to play chromatic passages. Unlike natural harmonics, they can be played with
vibrato.
This technique, like natural harmonics, works by canceling out the fundamental tone and one or more partial tones by deadening their modes of vibration. It is traditionally notated using two or three simultaneous
noteheads in one
staff: a normal notehead for the position of the firmly held finger, a square notehead for the position of the lightly pressed finger, and sometimes, a small notehead for the resulting pitch.
The most commonly used artificial harmonic, due to its relatively easy and natural
fingering, is that in which, "the fourth finger lightly touches the nodal point a perfect fourth above the first finger. (Resulting harmonic sound: two octaves above the first finger or new fundamental.),"
[Grimson, Samuel B. and Forsyth, Cecil (1920). ]
Modern Violin-Playing
', p.79-80. New York: H. W. Gray (Novello). . followed by the artificial harmonic produced when, "the fourth finger lightly touches the nodal point a perfect fifth above the first finger (Resulting harmonic sound: a twelfth above the first finger or new fundamental.),"
and, "the third finger lightly touches the nodal point a major third above the first finger. (Resulting harmonic sound: two octaves and a major third above the first finger or new fundamental.)"
Guitar
There are a few harmonic techniques unique to guitar.
Pinch harmonics
A pinch harmonic (also known as squelch picking, pick harmonic or squealy) is a guitar technique to achieve artificial harmonics in which the player's thumb or index finger on the picking hand slightly catches the string after it is picked,
, ''XtremeMusician.com''. Accessed: December 19, 2017. canceling (silencing) the fundamental frequency of the string, and letting one of the
overtones dominate. This results in a high-pitched sound which is particularly discernible on an electrically amplified guitar as a "squeal".
Tapped harmonics
Tapped harmonics were popularized by
Eddie Van Halen
Edward Lodewijk Van Halen ( , ; January 26, 1955 – October 6, 2020) was an American musician and songwriter. He was the guitarist, keyboardist, backing vocalist, and primary songwriter of the rock band Van Halen, which he co-founded along ...
. This technique is an extension of the
tapping technique. The note is fretted as usual, but instead of striking the string the excitation energy required to sound the note is achieved by tapping at a harmonic nodal point. The tapping finger bounces lightly on and off the fret. The open string technique can be extended to artificial harmonics. For instance, for an octave harmonic (12-fret nodal point) press at the third fret, and tap the fifteenth fret, as .
String harmonics driven by a magnetic field
This technique is used by effect devices producing a magnetic field that can agitate fundamentals and harmonics of steel strings. There are harmonic mode switches as provided by newer versions of the
EBow and by guitars built in sustainers like the
Fernandes Sustainer
An effects unit or effects pedal is an electronic device that alters the sound of a musical instrument or other audio source through audio signal processing.
Common effects include distortion/overdrive, often used with electric guitar in el ...
and the Moog Guitar. Harmonics control by harmonic mode switching and by the playing technique is applied by the
Guitar Resonator
The guitar is a fretted musical instrument that typically has six strings. It is usually held flat against the player's body and played by strumming or plucking the strings with the dominant hand, while simultaneously pressing selected strings ...
where harmonics can be alternated by changing the string driver position at the fretboard while playing.
See also
*
3rd bridge
The 3rd bridge is an extended playing technique used on the electric guitar and other string instruments that allows a musician to produce distinctive timbres and overtones that are unavailable on a conventional string instrument with two br ...
References
{{DEFAULTSORT:String harmonic
Harmonic series (music)
String performance techniques