What Sound Actually Is: The Science Every Musician Should Understand

Making a Scene Presents - What Sound Actually Is: The Science Every Musician Should Understand
Before the Microphone, Something Has to Move

Every recording begins with movement.

Before the microphone, the preamp, the audio interface, the computer, the waveform, the compressor, and the plugin with the picture of a rusty spaceship, something must vibrate.

A singer pushes air from the lungs past the vocal folds. Those folds open and close rapidly. A guitarist plucks a string, causing it to move back and forth. A drummer strikes a drumhead, which bends inward and springs back. A cymbal flexes in many directions at once. A piano hammer hits a string. A loudspeaker cone moves forward and backward.

That movement pushes and pulls on the air around it.

Air may look like empty space, but it is filled with tiny molecules. When a guitar string moves, it pushes nearby air molecules closer together. Those molecules bump into the next group, which bumps into another group. When the string moves back, it leaves a slightly less crowded area behind it. The result is a traveling pattern of higher and lower pressure.

That traveling pressure pattern is a sound wave.

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