Phaser (effect)
A phaser is an electronic sound processor used to filter a signal by creating a series of peaks and troughs in the frequency spectrum. The position of the peaks and troughs of the waveform being affected is typically modulated by an internal low-frequency oscillator so that they vary over time, creating a sweeping effect.
"Phasing" redirects here. For the compositional technique in which a repetitive phrase is played on two musical instruments in steady but not identical tempo, see Phasing (music).Similar effects[edit]
A specific type of phasing, flanging is a similar effect, in which the notches are linearly spaced. In a flanger effect, the notches are created by mixing the signal with a delayed version of itself. Flangers tend to sound more pronounced and natural, like the "jet plane whoosh" effect, whereas phasers tend to sound more subtle and otherworldly. For comparison of the two effects, check Flanging § Comparison with phase shifting.
The Uni-Vibe is an early phase-shifting effect that uses photoresistors for modulation.