Phase
Now, phase is a bit weird. In and of itself, phase doesn’t matter. However, phase is very important when you look at two separate waves: for example, two different audio sources into a single microphone, or a single audio source with multiple microphones at different distances.
Mathematically, for a sine wave, phase is the offset of the wave from the x-axis. When two waves are in phase, they will result in perfect constructive interference. You can basically add the waves together:
When waves are completely out of phase, you will get destructive interference and the waves will cancel each other out.
Most of the time, a pair of waves are not completely in phase or complete out of phase – they’re somewhere in between. Below is an example of what that could look like.
Y’know, except for the “gravity” part I guess.
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