We might mix for years, successfully creating recorded works of art, without fully appreciating what an audio signal actually is. But your technical mastery of all things audio will empower your creative power when you wish to experiment and bend rules. When you want to know more than enough about audio signals, read this appendix. It’s optional bonus material for overachievers.
When a guitar is strummed, a drum struck, or a trombone blown, we know sound will follow. The motion of the soundboard of the guitar, the vibration of the heads of the drum, and the resonance of the air within the plumbing of the trombone ultimately drive the air nearest our eardrums into action. We hear the air vibrate near us due to a chain ...