Flanging is a time-based audio effect that occurs when two identical signals are mixed together, but with one signal time-delayed by a small and gradually changing amount, usually smaller than 20 ms (milliseconds). This produces a swept 'comb filter' effect: peaks and notches are produced in the resultant frequency spectrum, related to each other in a linear harmonic series. Varying the time delay causes these to sweep up and down the frequency spectrum. Sound effects or audio effects are artificially created or enhanced sounds, or sound processes used to emphasize artistic or other content of movies, video games, music, or other media. ... In signal processing, a comb filter adds a delayed version of a signal to itself, causing constructive and destructive interference. ...

Part of the output signal is usually fed back to the input (a 're-circulating delay line'), producing a resonance effect which further enhances the intensity of the peaks and troughs. The phase of the fed-back signal is sometimes inverted, producing another variation on the flanging sound.

A flanger is a device dedicated to creating this sound effect.

Image File history File links Flanging_effect. ... Software development stages In computer programming, development stage terminology expresses how the development of a piece of software has progressed and how much further development it may require. ...

Comparison with phasing

Spectrograms of Phasing and Flanging effects

Flanging is one specific type of phasing. In phasing, the signal is passed through one or more all-pass filters which have non-linear phase response, and then added back to the original signal. This results in constructive and destructive interference that varies with frequency, giving a series of peaks and troughs in the frequency response of the system. In general, the position of these peaks and troughs do not occur in a harmonic series. Image File history File links Download high resolution version (512x778, 166 KB) Summary Spectrograms of the Flanging and Phasing effects. ... Image File history File links Download high resolution version (512x778, 166 KB) Summary Spectrograms of the Flanging and Phasing effects. ... It has been suggested that this article or section be merged with periodogram. ... A phaser is an audio signal processor used to filter a signal by attenuating a series of notches in the frequency spectrum. ... An all-pass filter is an electronic filter that passes all frequencies equally, but changes the phase relationship between various frequencies. ... Phase response is the relationship between the phase of a periodic input and an ouput signal passing through any device which accepts an input and produces an output signal such as an amplifier or a filter. ... Interference of two circular waves - Wavelength (decreasing bottom to top) and Wave centers distance (increasing to the right). ... Pitched musical instruments are usually based on a harmonic oscillator such as a string or a column of air. ...

In contrast, flanging relies on adding the signal to a uniform time-delayed copy of itself, which results in an output signal with peaks and troughs which are in a harmonic series. Extending the comb analogy, flanging uses a comb filter with regularly-spaced teeth, whereas phasing uses a comb filter with irregularly-spaced teeth.

In both phasing and flanging, the characteristics (phase response and time delay, respectively) are generally varied in time, leading to a audible sweeping effect.

To the ear, flanging and phasing sound similar, yet they are recognizable as distinct colorations.

Commonly, flanging is referred to as having a "jet plane"-like characteristic. For instance, Jimi Hendrix once referred to flanging as "airplanes going through your chromosomes".

Origin

The name flanging comes from the original method of creation. Originally, a signal would be recorded to two tape machines simultaneously. The playback-head output from these two recorders was then mixed together onto a 3rd recorder. In this form, minute differences in the motor speeds of each machine would result in a phasing effect when the signals were combined. The "flange" effect originated when an engineer would literally put a finger on the flange, or rim of one of the tape reels so that machine was slowed down, slipping out of sync by tiny degrees. A listener would hear a "drainpipe" swooping effect as shifting sum-and-difference harmonics were created. When the operator removed his/her finger the tape sped up again, making the effect move back in the other direction. Sony reel-to-reel tape recorder. ... Look up flange in Wiktionary, the free dictionary. ...

Older recording hardware could suffer from flanging as a undesired side effect when recording very long tracks. As the weight of the tape built up on one reel, the pressure on the capstans could cause flanging during mixdown or dubbing. This was one of the problems faced by studio engineers in the sixties and seventies when recording large concept pieces, as explained by Ian Anderson of Jethro Tull when recounting the studio challenges of recording Thick as a Brick. Capstans are found in the mechanisms of tape recorders in which they have a similar function to nautical capstans. ... Anderson (far right) with Jethro Tull in a recent promotional photo. ... This article or section does not cite its references or sources. ... Thick as a Brick (1972) is a concept album by the rock band Jethro Tull. ...

The classic flanging effect is believed to have been first perfected during 1966 by George Chkiantz, an engineer employed at Olympic Studios in Barnes, London, although it can be heard in The Big Hurt by Toni Fisher which rose to #3 in the Billboard chart in 1959. One of the first instances of the sound being used on a commercial pop recording was The Small Faces' 1967 single Itchycoo Park, recorded at Olympic and engineered by Chkiantz's colleague Glyn Johns. There are also claims that the technique was first pioneered by the BBC Radiophonic Workshop, who published their experiments on radio shows such as the Goon Show in freely available journals. ("Flange" was one of many words used out of context on the show to confuse/amuse the audience). George Chkiantz is a recording engineer in London who has been responsible for the engineering on a number of well-known albums, many of which are considered classics, owing in part to the high-quality of the recordings. ... Olympic Studios is a commercial recording studio located at 117 Church Road, in the south-western suburb of Barnes in London. ... Barnes is a suburb in south-west London in the London Borough of Richmond upon Thames. ... This article is about the capital of England and the United Kingdom. ... Small Faces, left to right: Ian McLagan, Steve Marriott, Kenney Jones, Ronnie Lane For the Scottish film, see Small Faces (film). ... Glyn Johns (born 1942 in Epsom, England) is a recording engineer and record producer who has worked with such artists as The Beatles, The Steve Miller Band, Led Zeppelin, The Rolling Stones, The Who, The Eagles, Eric Clapton, The Clash, Midnight Oil and the Blue Öyster Cult Linda Ronstadt, Emmylou... The BBC Radiophonic Workshop, one of the sound effects units of the BBC, was created in 1958 to produce effects and new music for radio, and was closed in March 1998, although much of its traditional work had already been outsourced by 1995. ... The Goon Show was a hugely popular and extremely influential British radio comedy programme, which was originally produced and broadcast by the BBC from 1951 to 1960 on the BBC Home Service. ...

If the frequency response of this effect is plotted on a graph, the trace resembles a comb, and so is called a comb filter. Once the operator takes his/her finger off, that player will speed up until its tachometer is back in phase with the master, and as this happens, the flanging effect will be repeated, with the harmonics swooping gradually higher until both signals pass momentarily through the silent perfect sync point again. It is often aesthetically better not to let the two tapes reach this point, but to start the reel-slowing again just before they get back into sync. Image File history File links Itchycoo_park. ... Software development stages In computer programming, development stage terminology expresses how the development of a piece of software has progressed and how much further development it may require. ... Tachometer showing engine rotations per minute (RPM), and a redline from 6000 RPM. A tachometer measures the speed of rotation of a shaft or disk (from Greek: tachos = speed, metron = measure), as in a motor or other machine. ...

In 1969, the record producer for The Litter, Warren Kendrick, devised a method to precisely control the flanging effect by placing two 15 IPS stereo Ampex tape recorders side-by-side. The take-up reel of recorder A and supply reel of recorder B were disabled, as were channel 2 of recorder A, channel 1 of recorder B and the erase head of recorder B. The tape was fed, left to right, across BOTH recorders and the identical signal was recorded on both channels of the tape; the signals were displaced by about 18 inches from each other. During the recording, a screwdriver was wedged between the tape recorders to make the tape run 'uphill' and 'downhill.' The same configuration was employed during the playback/mixdown to a third recorder. The screwdriver was moved back and forth to cause the two signals to diverge, then converge. The Litter was a psychedelic and garage rock band formed in 1966 in Minneapolis. ... Ampex is based in Redwood City, California. ... A basic screwdriver (slotted tip shown) A screwdriver is a device specifically designed to insert and tighten, or to loosen and remove, screws. ...

John Lennon of the Beatles used the term 'flanging' to refer to automatic double tracking, a technique developed at Abbey Road Studios by recording engineer Ken Townshend, in answer to producer George Martin's joking assertion that the ADT effect employed a "double-bifurcated sploshing flange". This usage of the term is coincidental. Standard flanging was used on the Beatles song "Blue Jay Way", written and sung by George Harrison. The first use of flanging effect in stereo is credited to producer Eddie Kramer who used the effect in the coda of Jimi Hendrix's song "Bold as Love" (1967). Kramer admitted in an 1990s interview that he read BBC Radiophonic Workshop technical journals for ideas and circuit diagrams. John Winston Ono Lennon, MBE (October 9, 1940 – December 8, 1980), (born John Winston Lennon, known as John Ono Lennon) was an iconic English 20th century rock and roll songwriter and singer, best known as the founding member of The Beatles. ... The Beatles were an English rock band from Liverpool whose members were John Lennon, Paul McCartney, George Harrison and Ringo Starr. ... Automatic double tracking (ADT) was an electronic system designed to augment the sound of voices and instruments during the recording process. ... The legendary recording studio Abbey Road Studios, created in November of 1931 by EMI in London, England is best known as the legendary recording studio used by the rock artists: The Beatles, Cliff Richard, Pink Floyd and The Shadows. ... Audio engineering is the branch of engineering dealing with the production of sound through mechanical means. ... This article or section does not cite its references or sources. ... Blue Jay Way is a song written by George Harrison; it was first released by the Beatles on their Magical Mystery Tour album and EP. The track was recorded on September 6, 1967 with vocals overdubbed September 7. ... This article or section does not cite its references or sources. ... Eddie Kramer is a legendary audio engineer and producer who has worked with KISS, Led Zeppelin, Jimi Hendrix, The Beatles, The Rolling Stones, David Bowie, Peter Frampton, Joe Cocker, Mott the Hoople, Curtis Mayfield, Santana, et al. ... This article or section is not written in the formal tone expected of an encyclopedia article. ... For the Jimi Hendrix song Bold as Love, see Axis: Bold as Love The cover of Bold as Love Frontispiece by Bryan Talbot Bold as Love is a novel by the British author Gwyneth Jones. ... The BBC Radiophonic Workshop, one of the sound effects units of the BBC, was created in 1958 to produce effects and new music for radio, and was closed in March 1998, although much of its traditional work had already been outsourced by 1995. ... The circuit diagram for a 4 bit TTL counter, a type of state machine A circuit diagram (also known as an electrical diagram or electronic schematic) is a pictorial representation of an electrical circuit. ...

In the 1970s, advances in solid state electronics made the flanging effect possible using integrated circuit technology. Solid state flanging devices fall into two categories: analog and digital. The flanging effect in most newer digital flangers relies on DSP technology. Flanging can also be accomplished using computer software. Even today, though, many studio practitioners prefer the sound of analog tape flanging, finding the serendipitous nature of human intervention more interesting than the clinical perfection created by purely electronic means. Tape flanging requires bulky hardware and takes quite a knack to get right, but some consider the results to be well worth the time and effort. The 1970s decade refers to the years from 1970 to 1979, inclusive. ... In electronics, solid state circuits are those that do not contain vacuum tubes. ... Integrated circuit showing memory blocks, logic and input/output pads around the periphery Microchips with a transparent window showing the integrated circuit inside. ... Digital signal processing (DSP) is the study of signals in a digital representation and the processing methods of these signals. ...

Note that the original tape-flanging effect sounds a little different from the later electronic and software re-creations. This is because, not only is the signal time-delayed, but the response characteristics at different frequencies of the magnetic tape and tape heads inevitably introduced some phase shifts into the signals as well. Thus, whilst the peaks and troughs of the comb filter are more-or-less in a linear harmonic series, there is a significant amount of non-linear behaviour too, causing the timbre of tape-flanging to sound more like a combination of what came to be known as flanging and phasing.

See also

• List of recordings with a prominent flanging effect
• Comb filter

These recordings contain a prominent Flanging effect: The main riff of Unchained by Van Halen On Killer Queen by Queen, on the line dynamite with a laser beam. ... In signal processing, a comb filter adds a delayed version of a signal to itself, causing constructive and destructive interference. ...

External links

• http://www.harmony-central.com/Effects/Articles/Flanging/
• Big Muff & Guitar Effects Museum.
• MXR Flanger - information on building a Flanger effect box for the electric guitar