Definition of phase shift

Phase shifting describes relative phase shift in superposing waves. Waves may be of electromagnetic (light, RF), acoustic (sound) or other nature. By superposing waves using different phase shifts the waves can add to (0° shift = "in phase") or cancel out each other (180°). A modulation of the relative phaseshift while superposing waves thus causes an amplitude modulation. Image File history File links Phase_shift. ... Image File history File links Phase_shift. ...

Phasing can be used as an audio effect. 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. ...

The term was often used to refer the original tape flanging effect heard on many psychedelic records of the late 1960s, notably "Itchycoo Park" by the Small Faces, and "Pictures of Matchstick Men" by Status Quo. However, as more practical solid-state electronics and latterly software were used to re-create an approximation of the unwieldy tape-flanging set-up, the term Phasing more specifically refers to a swept comb-filtering effect where there is no linear harmonic relationship between the teeth of the comb (compare this with flanging, where the teeth of the comb-filter are spaced along the frequency spectrum in a linear harmonic series). Flanging is a time-domain 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). ... Psychedelia is a term describing a category of music, visual art, fashion, and culture that is associated originally with the high 1960s, hippies, and the Haight-Ashbury neighborhood of San Francisco, California. ... The 1960s decade refers to the years from 1960 to 1969, inclusive. ... The Small Faces were a British rock and roll band of the 1960s, led by Steve Marriott and Ronnie Lane with Kenny Jones and original organist Jimmy Winston. ... To meet Wikipedias quality standards, this article or section may require cleanup. ... Spectrums of different comb filters In signal processing, a comb filter adds a slightly delayed version of a signal to itself, causing phase cancellations. ... Flanging is a time-domain 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). ...

The electronic phasing effect is created by splitting an audio signal into two, electronically shifting the phase of one signal (usually by passing it through an all-pass filter), and then recombining the two signals. The all-pass filter passes all frequencies unchanged in amplitude, but has a frequency-dependent, non-linear effect on the phase of each frequency. The result is a signal whose overall spectrum is shifted by various amounts at each frequency. For example, the phase of a frequency at the low end of the spectrum may be shifted by 1/4 of a wavelength, while a frequency at the high end of the spectrum may be shifted by 3/4 of a wavelength. An all-pass filter is an electronic filter that passes all frequencies equally, but changes the phase relationship between various frequencies. ...

When the filtered and non-filtered signals are recombined, the phase differences between them now cause peaks and notches of reinforcement and cancellation along the frequency spectrum (the so-called comb filter pattern). The degree of phase shift is periodically modulated (usually using an LFO), causing the peaks and notches to 'sweep' up and down the frequency spectrum, producing the characteristic rolling timbral changes of the phasing effect. Spectrums of different comb filters In signal processing, a comb filter adds a slightly delayed version of a signal to itself, causing phase cancellations. ... LFO may refer to: In electronic music, a low frequency oscillation. ...

A phaser is an electronic device used to produce this effect. It was originally produced by simply copying the sound onto two analogue tape decks and mixing them together with one tape running slightly faster than the other, so that one copy of the sound would overtake the other, resulting in a rising then falling effect caused by wave interference. DJs can achieve the same effect by playing two copies of the same record from the same point at the same time. A phaser is an audio signal processor used to filter a signal by attenuating a series of notches in the frequency spectrum. ... In communications, interference is anything which alters, modifies, or disrupts a message; as it travels along a channel, between a source and a receiver. ...

In motion picture or television production, the effect created by a phaser is often used to imply that the sound is synthetically generated (e.g. a computer or robot voice). The technique works because the frequency filtering produces sound we associate with mechanical sources, which only generate specific frequencies, rather than natural sources, which produce a range of frequencies. Film refers to the celluloid media on which movies are printed. ...

See also flanging, wave interference. Flanging is a time-domain 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). ... In communications, interference is anything which alters, modifies, or disrupts a message; as it travels along a channel, between a source and a receiver. ...

Audio download

• A short sample followed by a few different phasing effects on the same sample.

External link

• Harmony Central - phase shifting