In music, a drone is a harmonic or monophonic effect or accompaniment where a note or chord is continuously sounded throughout most or all of a piece. A drone may also be any part of a musical instrument used to produce this effect; an archaic term for this is burden (bourdon or burdon)   such as a "drone [pipe] of a bagpipe",   the pedal point in an organ, or the lowest course of a lute. Α burden is also part of a song that is repeated at the end of each stanza, such as the chorus or refrain. 
"Of all harmonic devices, it [a drone] is not only the simplest, but probably also the most fertile." 
A drone effect can be achieved through a sustained sound or through repetition of a note. It most often establishes a tonality upon which the rest of the piece is built. A drone can be instrumental, vocal or both. Drone (both instrumental and vocal) can be placed in different ranges of the polyphonic texture: in the lowest part, in the highest part, or in the middle. The drone is most often placed upon the tonic or dominant (play "Row, Row, Row Your Boat" with a drone on the tonic (help·info), on the dominant (help·info), or on both (help·info). Compare with changing chords (help·info).). A drone on the same pitch as a melodic note tends to both hide that note and to bring attention to it by increasing its importance.
A drone differs from a pedal tone or point in degree or quality. A pedal point may be a form of nonchord tone and thus required to resolve unlike a drone, or a pedal point may simply be considered a shorter drone, a drone being a longer pedal point.
The systematic use of drones originated in instrumental music of ancient Southwest Asia, and spread north and west to Europe and south to Africa.  It is used in Indian music and is played with the tanpura (or tambura) and other Indian drone instruments like the ottu, the ektar, the dotara (or dotar; dutar in Persian Central Asia), the surpeti, the surmandal (or swarmandal) and the shankh (conch shell). Most of the types of bagpipes that exist worldwide have up to three drones, making this one of the first instruments that comes to mind when speaking of drone music. In America, most forms of the African-influenced banjo contain a drone string. Since the 1960s, the drone has become a prominent feature in drone music and other forms of avant-garde music.
In vocal music drone is particularly widespread in traditional musical cultures, particularly in Europe, Polynesia and Melanesia. It is also present in some isolated regions of Asia (like among Pearl-divers in the Persian Gulf, some national minorities of South-West China, Taiwan, Vietnam, and Afghanistan).  [ page needed ]
Drone is also the term for the part of a musical instrument intended to produce the drone effect's sustained pitch, generally without the ongoing attention of the player. Different melodic Indian instruments (e.g. the sitar, the sarod, the sarangi and the rudra veena) contain a drone. For example, the sitar features three or four resonating drone strings, and Indian notes (sargam) are practiced to a drone. Bagpipes (like the Great Highland Bagpipe and the Zampogna) feature a number of drone pipes, giving the instruments their characteristic sounds. A hurdy-gurdy has one or more drone strings. The fifth string on a five-string banjo is a drone string with a separate tuning peg that places the end of the string five frets down the neck of the instrument; this string is usually tuned to the same note as that which the first string produces when played at the fifth fret, and the drone string is seldom fretted. The bass strings of the Slovenian drone zither also freely resonate as a drone. The Welsh Crwth also features two drone strings.
Composers of Western classical music occasionally used a drone (especially one on open fifths) to evoke a rustic or archaic atmosphere, perhaps echoing that of Scottish or other early or folk music. Examples include the following:
The best-known drone piece in the concert repertory is the Prelude to Wagner's Das Rheingold (1854) wherein low horns and bass instruments sustain an E♭ throughout the entire movement.  The atmospheric ostinato effect that opens Beethoven's Ninth Symphony, which inspired similar gestures in the opening of all the symphonies of Anton Bruckner, represents a gesture derivative of drones.
One consideration for composers of common practice keyboard music was equal temperament. The adjustments lead to slight mistunings as heard against a sustained drone. Even so, drones have often been used to spotlight dissonance purposefully.
Modern concert musicians make frequent use of drones, often with just or other non-equal tempered tunings. Drones are a regular feature in the music of composers indebted to the chant tradition, such as Arvo Pärt, Sofia Gubaidulina, and John Tavener. The single-tones that provided the impetus for minimalism through the music of La Monte Young and many of his students qualify as drones. David First, the band Coil, the early experimental compilations of John Cale ( Sun Blindness Music , Dream Interpretation, and Stainless Gamelan ), Pauline Oliveros and Stuart Dempster, Alvin Lucier ( Music On A Long Thin Wire ), Ellen Fullman, Lawrence Chandler and Arnold Dreyblatt all make notable use of drones. The music of Italian composer Giacinto Scelsi is essentially drone-based. Shorter drones or the general concept of a continuous element are often used by many other composers. Other composers whose music is entirely based on drones include Charlemagne Palestine and Phill Niblock. The Immovable Do by Percy Grainger contains a sustained high C (heard in the upper woodwinds) that lasts for the entirety of the piece. Drone pieces also include Loren Rush's Hard Music (1970)  and Folke Rabe's Was?? (1968),  as well as Robert Erickson's Down at Piraeus.  The avant-garde guitarist Glenn Branca also used drones extensively. French singer Camille uses a continuous B throughout her album Le_Fil.
Drones continue to be characteristic of folk music. Early songs by Bob Dylan employ the effect with a retuned guitar in "Masters of War" and "Mr. Tambourine Man".[ citation needed ] The song "You Will Be My Ain True Love", written by Sting for the 2003 movie Cold Mountain and performed by Alison Krauss and Sting, uses drone bass.[ citation needed ]
Drones are used widely in the blues and blues-derived genres. Jerry Lee Lewis featured drones in solos and fills.  Drones were virtually absent in original rock and roll music,[ citation needed ] but gained popularity after the Beatles used drones in a few popular compositions (for example, "Blackbird" has a drone in the middle of a texture throughout the whole song, "Tomorrow Never Knows" makes use of tambura). They also used high drone for the dramatic effect in some sections of several of their compositions (like the last verses of "Yesterday" and "Eleanor Rigby").[ citation needed ] Roy Ayers' Everybody Loves the Sunshine (1976) has a high sustained synth string note through most of the song.  The rock band U2 uses drones in their compositions particularly widely.[ citation needed ] In the Led Zeppelin song "In The Light", a keyboard drone is used throughout the song, mostly in the intro.[ citation needed ]
Drones are used by a number of music education programs for ear training and pitch awareness, as well as a way to improvise ensemble music.  A shruti box is often used by vocalists in this style of musical training. Drones, owing to their acoustic properties and following their longstanding use in ritual and chant, can be useful in constructing aural structures outside common practice expectations of harmony and melody.  [ verification needed ]
The banjo is a stringed instrument with a thin membrane stretched over a frame or cavity to form a resonator. The membrane is typically circular, and usually made of plastic, or occasionally animal skin. Early forms of the instrument were fashioned by African Americans in the United States. The banjo is frequently associated with folk, bluegrass and country music, and has also been used in some rock, pop and hip-hop. Several rock bands, such as the Eagles, Led Zeppelin, and the Grateful Dead, have used the five-string banjo in some of their songs. Historically, the banjo occupied a central place in Black American traditional music and the folk culture of rural whites before entering the mainstream via the minstrel shows of the 19th century. Along with the fiddle, the banjo is a mainstay of American styles of music, such as bluegrass and old-time music. It is also very frequently used in Dixieland jazz, as well as in Caribbean genres like biguine, calypso and mento.
The clavichord is a stringed rectangular keyboard instrument that was used largely in the Late Middle Ages, through the Renaissance, Baroque and Classical eras. Historically, it was mostly used as a practice instrument and as an aid to composition, not being loud enough for larger performances. The clavichord produces sound by striking brass or iron strings with small metal blades called tangents. Vibrations are transmitted through the bridge(s) to the soundboard.
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.
The sitar is a plucked stringed instrument, originating from the Indian subcontinent, used in Hindustani classical music. The instrument was invented in medieval India, flourished in the 18th century, and arrived at its present form in 19th-century India. Khusrau Khan, an 18th century figure of Mughal Empire has been identified by modern scholarship as the originator of Sitar. According to most historians he developed sitar from setar, an Iranian instrument of Abbasid or Safavid origin. Another view supported by a minority of scholars is that Khusrau Khan developed it from Veena.
Zithers are a class of stringed instruments. Historically, the name has been applied to any instrument of the psaltery family, or to an instrument consisting of many strings stretched across a thin, flat body. This article describes the latter variety.
Clawhammer, sometimes called down-picking, overhand, or frailing, is a distinctive banjo playing style and a common component of American old-time music.
A capo is a device a musician uses on the neck of a stringed instrument to transpose and shorten the playable length of the strings—hence raising the pitch. It is a common tool for players of guitars, mandolins, mandolas, banjos, ukuleles and bouzoukis. The word derives from the Italian capotasto, which means the nut of a stringed instrument. The earliest known use of capotasto is by Giovanni Battista Doni who, in his Annotazioni of 1640, uses it to describe the nut of a viola da gamba. The first patented capo was designed by James Ashborn of Wolcottville, Connecticut year 1850.
A pull-off is a stringed instrument playing and articulation technique performed by plucking or "pulling" the finger that is grasping the sounding part of a string off the fingerboard of either a fretted or unfretted instrument. This intermediate- to advanced playing technique is done using the tip of a finger or fingernail on the fretting hand. Pull-offs are done to facilitate the playing of embellishments and ornaments such as grace notes. Pull-offs may be notated in sheet music or improvised by the performer, depending on the musical style and context.
The Appalachian dulcimer is a fretted string instrument of the zither family, typically with three or four strings, originally played in the Appalachian region of the United States. The body extends the length of the fingerboard, and its fretting is generally diatonic.
The tanpura, also referred to as tambura and tanpuri, is a long-necked plucked string instrument, originating in India, found in various forms in Indian music.
Sympathetic strings or resonance strings are auxiliary strings found on many Indian musical instruments, as well as some Western Baroque instruments and a variety of folk instruments. They are typically not played directly by the performer, only indirectly through the tones that are played on the main strings, based on the principle of sympathetic resonance. The resonance is most often heard when the fundamental frequency of the string is in unison or an octave lower or higher than the catalyst note, although it can occur for other intervals, such as a fifth, with less effect.
Fingerstyle guitar is the technique of playing the guitar or bass guitar by plucking the strings directly with the fingertips, fingernails, or picks attached to fingers, as opposed to flatpicking. The term "fingerstyle" is something of a misnomer, since it is present in several different genres and styles of music—but mostly, because it involves a completely different technique, not just a "style" of playing, especially for the guitarist's picking/plucking hand. The term is often used synonymously with fingerpicking except in classical guitar circles, although fingerpicking can also refer to a specific tradition of folk, blues and country guitar playing in the US. The terms "fingerstyle" and "fingerpicking" also applied to similar string instruments such as the banjo.
Tamburica or tamboura, refers to a family of long-necked lutes popular in Southern Europe and Central Europe, especially Serbia, Bosnia and Herzegovina, Croatia, Slovenia, and Hungary. It is also known in Burgenland, Austria. All took their name and some characteristics from the Persian tanbur but also resemble the mandolin and guitar in the sense that its strings are plucked and often paired. The frets may be moveable to allow the playing of various modes. The variety of tamburica shapes known today were developed in Serbia and Croatia by a number of indigenous contributors near the end of the 19th century.
Guitar tunings are the assignment of pitches to the open strings of guitars, including acoustic guitars, electric guitars, and classical guitars. Tunings are described by the particular pitches that are made by notes in Western music. By convention, the notes are ordered and arranged from the lowest-pitched string to the highest-pitched string, or the thickest string to thinnest, or the lowest frequency to the highest. This sometimes confuses beginner guitarists, since the highest-pitched string is referred to as the 1st string, and the lowest-pitched is the 6th string.
Chorus is an audio effect that occurs when individual sounds with approximately the same time, and very similar pitches, converge. While similar sounds coming from multiple sources can occur naturally, as in the case of a choir or string orchestra, it can also be simulated using an electronic effects unit or signal processing device.
Among alternative tunings for the guitar, an open G tuning is an open tuning that features the G-major chord; its open notes are selected from the notes of a G-major chord, such as the G-major triad (G,B,D). For example, a popular open-G tuning is
The çifteli is a plucked string instrument, with only two strings, played mainly by the Albanians of northern and central Albania, Southern Montenegro, parts of North Macedonia and Kosovo.
Guitar picking is a group of hand and finger techniques a guitarist uses to set guitar strings in motion to produce audible notes. These techniques involve plucking, strumming, brushing, etc. Picking can be done with:
The samica is a small stringed and fretted traditional Croatian and Serbian folk instrument. Its overall shape is similar to that of the dangubica, and has up to four strings. One of these strings is used to play a melody, the rest being used as drones, playing a single note. The samica is often played to accompany dancing and singing. Along with the dangubica, the samica is one of the forerunners of the modern tamburitza.
The tambura is a stringed instrument that is played as a folk instrument in Bosnia and Herzegovina, Bulgaria, Croatia, North Macedonia, and Serbia. It has doubled steel strings and is played with a plectrum, in the same manner as a mandolin.
This article incorporates text from a publication now in the public domain : Chambers, Ephraim, ed. (1728). "Burden". Cyclopædia, or an Universal Dictionary of Arts and Sciences (1st ed.). James and John Knapton, et al.