Digital Audio Fundamentals

In this course, Digital Audio Fundamentals, we’ll follow the journey of audio from humble beginnings where they are just analog signals and follow their transformation into the digital realm. This course is a deep dive into the world of digital audio and all the theory, practicalities and nuances associated with it.

We’ll look at what it means for audio to be in the digital domain and how it’s different, or rather similar to audio in the analog domain. How do we even define it, and what are the hallmarks of digital audio. We’ll see how we need to give up the concept of time as being continuous and instead think about time in tiny slices, spaced apart. We’ll learn about the Nyquist sampling theorem which governs every aspect of digital signal processing, so we’ll take a deep dive into the process of sampling and talk about the motivations for using different sample rates for your projects. We’ll take a look at aliasing, a common problem that arises from the poor consideration of sampling, and understand why this happens using illustrations and example and try to adopt solutions that get rid of them for good.

We’ll move on to the realm of sample amplitude measurements, where we talk about quantization of audio and the resolution of the digitization process. We’ll see how it’s interrelated with noise and dynamic range of digital signals. We’ll look at the binary and bitwise representation of audio sample data, and explore the concept of bit depth. We'll examine the real world effects and artifacts of choosing different bit depths and listen to what quantization error sounds like. There are a couple of miscellaneous topics where I introduce ways of reducing this noise by using techniques like dithering and noise shaping.

We’ll bring all of these concepts together to talk about encoding, and discuss a simple yet powerful encoding mechanism called pulse code modulation for packaging digital data for the purposes of transmission and storage. Speaking about storage, we’ll explore how digital audio is stored and accessed in a computer file system by looking at containers and file formats.

This course is for anybody working in the realm of digital audio. Be it a musician, who wants to record his instruments and want to understand the process, or a seasoned producer, who wants to refresh and relearn some of the concepts, or a software engineer who wants to get into audio programming and want a strong foundation.