Phaser is an effect created by a series of all pass filters (phase shifters). When the output of the filters is mixed with the dry signal sharp notches are created in the frequency spectrum of the output; by modulating the center frequencies of the filters the notches move giving a sense of motion to the effect. Four types of phasing effects are supported Positive [POS], Negative [NEG], Feedback [FEEDBK], Bi-phase [BIPHAZ] and PhaseX0 [PHASX0].