Howtosignalprocessing
Why are there two lines in Garageband?
On waveform is a mono Audio Region, double waveform is a stereo Audio Region. If you record on an Audio Track that is set to a mono input in the Recording Source, it will record a mono Audio Region. If it is set to a stereo input, then it will create a stereo Audio Region.
Why is my waveform uneven?
In combining different frequency signals with differing phase relationships, the result is often a distinctly asymmetrical waveform, and that waveform asymmetry often changes and evolves over time, too. That's just what happens when complex related signals are superimposed.
