What is Sound?

The Science of Sound: How Audio is Recorded and Reproduced

When I was 12, I remember asking my older brother “What is sound? And, how, from this random squiggle of lines, do you get the sound of an orchestra with a variety of instruments?” In essence, not only did I want to know what sound is but also how sound is recorded and reproduced. Unfortunately, I don’t remember his explanation clearing things up. Now, years later, with the help of one of our Friends of CircuitBread, PUI Audio, we are able to answer my 12 year old self. Using a series of examples and animations, we show what sound is physically, how it’s a longitudinal wave that can be recorded as a transverse voltage wave, and how different sounds can be recreated with a single signal. We use some samples from PUI Audio to show how microphones record sound and how speakers can play that sound back.