Digital Signal Processing

Written by Travis M. Moore
Last edited 30-Jan-2021

Computerizing Sound

Think about the benefits to humanity that arose from the discovery of how to record sound. Anyone can enjoy music without having to attend a live event or gather together an orchestra. Individuals with visual impairment can listen to books being read whenever they like. The radio or T.V. can transmit important information, or just fill the silence of an empty house for your pets. Everything from warning sounds to academic lectures have been recorded, allowing the ability to be dispersed and used at a later date.

Have you ever wondered how this amazing feat is accomplished? You already know that sound is essentially vibrations traveling through a medium, but how do you "store" that for later? For that matter, how did they record sound in the early 1900s before the advent of the computer? Do computers use the same methods as vinyl records? (No. Go through the lessons for more specifics!) Even though recorded audio is all around us, many people are unfamiliar with the principles of recording sound. Lucky for you, that's exactly what you'll learn in this module.

You'll notice this module is called "digital signal processing," which deals with computer recordings, rather than vinyl recordings. We'll discuss the two ways to represent sound (digital and analog), as well as how to convert from one representation to the other (e.g., making an mp3 of a record). But wait, there's more! Digital signal processing isn't limited to acoustic signals. The information covered here can be applied to a variety of signals. For example, the information in this module is also necessary to understand how to record electrical signals, which is an essential part of recording evoked potentials.