Dipole is a through-zero flanger. It combines two delay lines, with one able to run earlier or later in time relatively to the other, plus a trick positive or negative feedback loop. Right around the zero time difference between the delays, this algorithm produces a “jet fly-by” effect (+) or full sound cancellation (–). Originally, through-zero flanging was achieved using a pair of tape machines, by manually controlling the difference in their speed. Here, a sine wave LFO is used to sweep the effect.