The DeltaLab PS-1 Phase Shifter is a compact analog modulation pedal designed to deliver classic four-stage phasing effects. It features simple rate and depth controls that allow players to move from slow subtle movement to faster swirling phase textures. The pedal was produced in Japan during the early compact-pedal era and is known for its straightforward signal path and warm modulation character. Its design reflects late 1970s and early 1980s phase shifter circuits commonly used with guitar and keyboards. The PS-1 was marketed as an affordable alternative to larger phaser units of the time. Production has long since been discontinued.