ABSTRACT
Modulated delay lines are at the heart of a few other effects. Although neither phasers nor tremolos are based on delay lines, their operation is based on modulation. Vibrato is the effect caused by rapid and subtle alteration of pitch. Not all singers are fans of the effort involved with real double-tracking. The actual idea of multiple singers singing in unison was established well before harmony was introduced into Western compositions. Just like with guitars, flanging is mostly used as a distinct effect in the mix. Flanging is based on comb filtering created as a result of very short delay times. By way of analogy, the flanging effect is like a siren where the depth determines how low and high the siren goes, and the rate determines how quickly it goes. Flanging and phasing are twin effects, sounding very similar, yet different.
