When recording audio for film, television, or documentaries, dialogue editors frequently deal with multi-microphone configurations. The most common setup involves a and one or more lavalier (body) microphones .

Traditionally, dialogue editors had to manually zoom into waveforms in their Digital Audio Workstation (DAW) and slide clips forward or backward by milliseconds. However, if the actor or the boom operator moves during a take, the time delay changes continuously, making manual correction nearly impossible. 2. Enter Auto-Align Post v1.0.1

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Mixing these two out-of-sync signals causes comb filtering —a destructive interference pattern that makes dialogue sound hollow, thin, or phasey.

Sound travels through air at approximately 343 meters per second. Because the boom microphone sits further from the actor's mouth than the lavalier mic, the same sound arrives at the boom mic slightly later.