Sound waves are created in air (air is a propagating medium) by the vibration of an object (like the cone of a speaker)
A vibrating object creates changes in air pressure which causes the surrounding air molecules to move in a specific pattern that radiates outward from the object in all directions.
This pattern can be described in two ways:
- Compression (don’t confuse this with the audio processor) – is when air molecules are pushed closer together
- Rarefaction – is when the air molecules separate and move away from each other.
The completion of a full compression and a rarefaction pattern is called a soundwave.