Pinch harmonic
From Wikipedia, the free encyclopedia
 |
|
||||
| Problems listening to this file? See media help. | |||||
A pinch harmonic or pick harmonic[1] is a guitar technique pioneered by Roy Buchanan on the 1962 recording of "Potato Peeler" [2] in which the player's thumb or index finger on the picking hand, slightly catches the string after it is picked, cancelling the fundamental of the string, and letting one of the overtones to dominate in a similar way to how altissimo notes are produced on woodwind instruments. This results in a high pitched sound. By using string bending, a whammy bar, a wah-wah pedal, or other effects, electric guitarists are able to modulate the pitch, frequency, and timbre of pinch harmonics, resulting in a variety of sounds, the most common being a very high-pitched squeal.
Contents |
[edit] Use in rock and metal
The technique is possible on any fretted stringed instrument, but is most widely employed by electric guitarists, especially in heavy metal and rock music where heavy distortion ensures that the otherwise subtle harmonic is greatly amplified. One of the earliest guitarists to frequently use pinched harmonics in his playing was Leslie West of Mountain, active during the early 1970s. But it was artists such as Eddie Van Halen, Dimebag Darrell and Steve Vai who made the technique popular, utilizing the tremolo arm and high gain amps together with the pinch harmonic. This ended up producing wild, screaming, horse-like wails from the instrument. Steve Vai composed a track named "Bad Horsie" which uses heavy pinch harmonic techniques. A pinch harmonic was used at the beginning of the second solo of Pink Floyd's famous Comfortably Numb of 1979.
Pinch harmonics are used extensively in death metal. The technique's use in death metal is notable in that pinch harmonic notes are included in riffs, rather than being reserved for solos. Combined with the rather low tunings most of these guitarists use, and the fact that they are usually played by both rhythm guitarists (if there are two), the pinch harmonic notes leap out, creating more complex and twisted melodic contours than otherwise possible. The technique is also used commonly in other sub-genres of heavy metal, particularly by guitarists such as Glenn Tipton, Zakk Wylde, Richie Sambora and Dimebag Darrell. One guitarist of the rock genre who is widely known for his use of pinch harmonics is Billy Gibbons of ZZ Top, who uses them frequently in guitar solos. There are also other types of harmonics such as natural harmonics and tapped harmonics.
[edit] Technique
A pinch harmonic is produced when the thumb of the picking hand lightly touches against the string immediately after it is picked. This action is sufficient to silence the fundamental and all overtones except those which have a node at that location. This is generally accomplished by holding the guitar pick so that very little of its tip protrudes between the thumb and forefinger (roughly 3-5 mm), allowing the thumb to brush the string immediately after it is picked.
The technique must be performed at one of the appropriate harmonic nodes for the note to sound. For example, to produce a pinch harmonic which is one octave higher than the fundamental of a string which is stopped at the third fret of a guitar, the string must be plucked halfway between the third fret and the bridge (i.e. 15th fret as the neck is logarithmic). Other overtones of the same fundamental note may be produced in the same way at other nodes along the string. The point at which the string is plucked therefore varies depending on the desired note. Most harmonics have several accessible nodes evenly spaced on the string; so it is no surprise that the nodes used in practice are normally those around where the string is normally picked (around the pickups on an electric guitar), rather than those above the neck as these are the easiest to access with the picking hand from normal playing.
Overtones with a frequency of a multiple of the intended overtone (i.e. its own harmonics) will share the nodes of the lower overtone, so won't be muted. They will, however, be at a much lower volume and since they form the selected overtone's own harmonic series, don't detract from the sound of the note. If the string is pinched at the antinode of the intended overtone, no higher overtones will sound.
A single harmonic overtone is far quieter than a normal note which contains many overtones. For this reason, amplification which causes quieter notes to be louder in comparison with notes that are actually louder (distortion or compression for instance) is often used to improve the overall sound. Thicker strings, stronger pickups and adjustment to amplifier settings (increasing gain) are some ways of doing this. It is important to note that as there is only one fundamental sounding, it will have a different volume through different pickups, depending on the proximity of nodes or antinodes to the pickup. The different volumes of overtones are the reason pickups sound different. The outcome of this is that if a node is directly over a pickup, it won't sound through that pickup.
[edit] References
[edit] External links
- Guitar Harmonics Lesson - A lesson covering the various types of harmonics that can be played on a guitar and how to play them.
- Pinch Harmonics at Cyberfret
- Animated Pinch Harmonic Examples at ActionTab
- Guitar Amplifiers explained at GM Arts Home Page
