Phasers and flangers are classic audio effects. Although they achieve their results in different ways, both phasers and flangers work by effectively applying a number of moving notches or peaks to the spectrum of the input signal. By manipulating the motion and magnitude of these spectral adjustments, it is possible to create a psychoacoustic sensation of motion which appears to proceed up or down in pitch “forever”, similar to the visual effect produced by a rotating barber pole. This effect is similar to the aural illusion of Shepherd-Risset tones, whose pitches appear to ascend or descend endlessly.
In the Spring of 2016 I developed a pair of VST audio plugins which generate these endless phasing and flanging audio illusions. The plugins were developed in the FAUST audio programming language and feature a number of user-adjustable parameters. The plugins were presented as a term project for the ECE 476 Audio Software Design II course at University of Rochester.