Phasing
Encyclopedia
In the compositional technique phasing, the same part (a repetitive phrase) is played on two musical instrument
s, in steady but not identical tempo
. Thus, the two instruments gradually shift out of unison, creating first a slight echo as one instrument plays a little behind the other, then a doubling with each note heard twice, then a complex ringing effect, and eventually coming back through doubling and echo into unison. Phasing is the rhythmic equivalent of cycling through the phase of two waveforms as in phasing. Note that the tempi of the two instruments are almost identical, so that both parts are perceived as being in the same tempo: the changes only separate the parts gradually. In some cases, especially live performance where gradual separation is extremely difficult, phasing is accomplished by periodically inserting an extra note into the phrase of one of the two players playing the same repeated phrase, thus shifting the phase by a single beat at a time, rather than gradually.
The technique was first used in 1959 on The Big Hurt by Miss Toni Fisher.
It was subsequently popularized by composer Steve Reich
. In Reich's tape music
, where the composer sets off several copies of the same tape loop simultaneously on different machines. Over time, the slight differences in the speed of the different tape machines causes a flanging
effect and then rhythmic separation to occur. Examples include Reich's Come Out
and It's Gonna Rain
. This technique was then extended to acoustic instruments as described in the above paragraph and later the change in phase was made immediate, rather than gradual, as in Reich's Clapping Music.
As the cycle unfolds, often other melodies will be created by the differing instances of the original phrase being played together. As in Steve Reich's Violin Phase, the composer will sometimes have an additional instrument or live performer with the tape who playing these secondary, extracted melodies to accentuate them.
Music writer Kyle Gann
has pointed out on later use of phase shifting technique: "Though not widely used in minimalist works per se, it survived as an important archetype in postminimal music (e.g. William Duckworth
's Time Curve Preludes, John Luther Adams
's Dream in White on White, Kyle Gann
's Time Does Not Exist)." Petri Kuljuntausta
's Violin Tone Orchestra, Words and When I Am Laid In Earth are all phasing works and composed with the help of digital sampler, or computer, and multitrack technology. His electronic multichannel music for video installation Eight Rooms is based on spatial phasing, where the phase shifted sounds surrounds the listeners and moves around them. Kuljuntausta's phase shifting method is based on Nano Tuning of sounds.
An example of phasing in popular music
is "The True Wheel" on Brian Eno
's album Taking Tiger Mountain (By Strategy)
. Another one is the final track on Sufjan Stevens
' Illinoise.
The playing of different repeated phrases in the same tempo but having different metrical lengths (beats in the bar), as in the music of Philip Glass
and others, is not phasing but may be considered polymeters.
The effect is similar to that heard when a Shortwave station undergoes fading. As the signal takes multiple paths through the ionosphere, the different time delays cause the signal to exhibit the characteristic phasing sound.
Musical instrument
A musical instrument is a device created or adapted for the purpose of making musical sounds. In principle, any object that produces sound can serve as a musical instrument—it is through purpose that the object becomes a musical instrument. The history of musical instruments dates back to the...
s, in steady but not identical tempo
Tempo
In musical terminology, tempo is the speed or pace of a given piece. Tempo is a crucial element of any musical composition, as it can affect the mood and difficulty of a piece.-Measuring tempo:...
. Thus, the two instruments gradually shift out of unison, creating first a slight echo as one instrument plays a little behind the other, then a doubling with each note heard twice, then a complex ringing effect, and eventually coming back through doubling and echo into unison. Phasing is the rhythmic equivalent of cycling through the phase of two waveforms as in phasing. Note that the tempi of the two instruments are almost identical, so that both parts are perceived as being in the same tempo: the changes only separate the parts gradually. In some cases, especially live performance where gradual separation is extremely difficult, phasing is accomplished by periodically inserting an extra note into the phrase of one of the two players playing the same repeated phrase, thus shifting the phase by a single beat at a time, rather than gradually.
The technique was first used in 1959 on The Big Hurt by Miss Toni Fisher.
It was subsequently popularized by composer Steve Reich
Steve Reich
Stephen Michael "Steve" Reich is an American composer who together with La Monte Young, Terry Riley, and Philip Glass is a pioneering composer of minimal music...
. In Reich's tape music
Tape Music
Tape Music is an experimental 10" vinyl release by Jack Dangers. The vinyl release was coupled with the album Sounds Of The 20th Century No2 when released as a flexi disc vinyl....
, where the composer sets off several copies of the same tape loop simultaneously on different machines. Over time, the slight differences in the speed of the different tape machines causes a flanging
Flanging
Flanging is an audio effect produced by mixing two identical signals together, with one signal delayed by a small and gradually changing period, usually smaller than 20 milliseconds. This produces a swept comb filter effect: peaks and notches are produced in the resultant frequency spectrum,...
effect and then rhythmic separation to occur. Examples include Reich's Come Out
Come Out (Reich)
Come Out is a 1966 piece by American composer Steve Reich. He was asked to write this piece to be performed at a benefit for the retrial of the Harlem Six, six black youths arrested for committing a murder during the Harlem Riot of 1964 for which only one of the six was responsible...
and It's Gonna Rain
It's Gonna Rain
It's Gonna Rain is a minimalist musical composition for magnetic tape written by Steve Reich in 1965. It lasts approximately 17 minutes and 50 seconds. It was Reich's first major work and a landmark in minimalism and process music.-Analysis:...
. This technique was then extended to acoustic instruments as described in the above paragraph and later the change in phase was made immediate, rather than gradual, as in Reich's Clapping Music.
As the cycle unfolds, often other melodies will be created by the differing instances of the original phrase being played together. As in Steve Reich's Violin Phase, the composer will sometimes have an additional instrument or live performer with the tape who playing these secondary, extracted melodies to accentuate them.
Music writer Kyle Gann
Kyle Gann
Kyle Eugene Gann is an American professor of music, critic and composer born in Dallas, Texas. As a critic for The Village Voice and other publications he has been a supporter of progressive music including such Downtown movements as postminimalism and totalism.- As composer :As a composer his...
has pointed out on later use of phase shifting technique: "Though not widely used in minimalist works per se, it survived as an important archetype in postminimal music (e.g. William Duckworth
William Duckworth
William Duckworth is an American composer who also is an author, educator and Internet pioneer. He has written more than 200 pieces of music and is credited with the composition of the first postminimal piece of music, The Time Curve Preludes , for piano...
's Time Curve Preludes, John Luther Adams
John Luther Adams
John Luther Adams is a composer whose music is inspired by nature, especially the landscapes of Alaska where he has lived since 1978.-Biography:...
's Dream in White on White, Kyle Gann
Kyle Gann
Kyle Eugene Gann is an American professor of music, critic and composer born in Dallas, Texas. As a critic for The Village Voice and other publications he has been a supporter of progressive music including such Downtown movements as postminimalism and totalism.- As composer :As a composer his...
's Time Does Not Exist)." Petri Kuljuntausta
Petri Kuljuntausta
Petri Kuljuntausta is a composer, musician, sound artist and author of three books on electronic music and sound art. Since 1990's he has belonged to a new generation of composers in Finland interested in experimental and electronic music....
's Violin Tone Orchestra, Words and When I Am Laid In Earth are all phasing works and composed with the help of digital sampler, or computer, and multitrack technology. His electronic multichannel music for video installation Eight Rooms is based on spatial phasing, where the phase shifted sounds surrounds the listeners and moves around them. Kuljuntausta's phase shifting method is based on Nano Tuning of sounds.
An example of phasing in popular music
Popular music
Popular music belongs to any of a number of musical genres "having wide appeal" and is typically distributed to large audiences through the music industry. It stands in contrast to both art music and traditional music, which are typically disseminated academically or orally to smaller, local...
is "The True Wheel" on Brian Eno
Brian Eno
Brian Peter George St. John le Baptiste de la Salle Eno , commonly known as Brian Eno or simply as Eno , is an English musician, composer, record producer, singer and visual artist, known as one of the principal innovators of ambient music.Eno studied at Colchester Institute art school in Essex,...
's album Taking Tiger Mountain (By Strategy)
Taking Tiger Mountain (By Strategy)
Taking Tiger Mountain is the second solo album by Brian Eno. Produced by Eno, it was originally released by Island Records in November 1974 in a gatefold sleeve. Unlike his previous album Here Come the Warm Jets, Eno used a core band of five instrumentalists and used fewer guest musicians...
. Another one is the final track on Sufjan Stevens
Sufjan Stevens
Sufjan Stevens is an American singer-songwriter and musician born in Detroit, Michigan. Stevens first began releasing his music on Asthmatic Kitty, a label co-founded with his stepfather, beginning with the 1999 release, A Sun Came...
' Illinoise.
The playing of different repeated phrases in the same tempo but having different metrical lengths (beats in the bar), as in the music of Philip Glass
Philip Glass
Philip Glass is an American composer. He is considered to be one of the most influential composers of the late 20th century and is widely acknowledged as a composer who has brought art music to the public .His music is often described as minimalist, along with...
and others, is not phasing but may be considered polymeters.
The effect is similar to that heard when a Shortwave station undergoes fading. As the signal takes multiple paths through the ionosphere, the different time delays cause the signal to exhibit the characteristic phasing sound.