The 297 Infinite Phase Shifter creates barber-pole phasing — a comb filter whose notches continuously move in one direction without net positional change

The 297 Infinite Phase Shifter displaces the phase of a signal by up to 1800 degrees and can combine the shifted signal with the original to create a comb filter effect. Its distinctive feature is barber-pole phasing: special circuitry causes the phase shift and consequent filter peaks/notches to continuously move in one direction (up or down) while never net-advancing — the auditory equivalent of an Escher staircase. Rate is variable up to 2.5 octaves per second and voltage-controllable. Standard cyclic phasing (LFO sweeping back and forth) is also available. The 297 is a non-e module and does not save parameters to presets.

Examples

Set the 297 to barber-pole mode at a slow upward rate with light feedback (resonance) — the filter notches appear to climb indefinitely, creating a sense of endless rising tension without net pitch change.

Assessment

Contrast the 297’s barber-pole phasing mode with standard cyclic phasing in terms of perceived motion. Explain what comb filter characteristics the 297 creates when the phase-shifted signal is recombined with the original.