Not just a phase. One of the very first BOSS pedals to hit the market back in 1977 was the PH-1 Phase Shifter. The BOSS PH-3 is the successor of the scarce PH-1 model which was discontinued in 1981. Unlike the PH-1, the PH-3 is a digital pedal, that gives the player a much greater control and array of sound options. A mode switch allows you to choose between 4, 8, 10 and 12-stage phases as well as Rise and Fall modes (so always going up or always going down) and a wild step mode that applies sweep cycle that proceeds in "stairstep" (easier heard than explained). Thanks to tap tempo and optional expression pedal features, it is safe to say that the BOSS PH-3 delivers the best of both vintage and modern worlds.