Digital Audio Primer from Xiph.Org
I've seen these videos from Xiph.org pop up a few times over the last few years, and wanted to share them as they're probably the clearest, and most concise summations of digital audio that I've ever seen.
These topics can certainly be confusing, and difficult to grasp. I highly recommend watching both videos, but the second one is the most relevant to music and audio production.
Xiph.Org Foundation is a non-profit organization that produces free multimedia formats and software tools. It focuses on the Ogg family of formats, and the most successful one has been Vorbis, an open and freely licensed audio format and codec designed to compete with the patented WMA, MP3
and AAC. As of 2013, the current development work is focusing on Daala, an open and patent-free video format and codec designed to compete with the patented High Efficiency Video Coding and VP9. (From Wikipedia)
This first video from Xiph.Org presents the technical foundations of modern digital media via a half-hour firehose of information. One community member called it "a Uni lecture I never got but really wanted."
The program offers a brief history of digital media, a quick summary of the sampling theorem, and a myriad of details on low level audio and video characterization and formatting. It's intended for budding geeks looking to get into video coding, as well as the technically curious who want to know more about the media they wrangle for work or play.
Continuing in the "firehose" tradition of Episode 01, Xiph.Org's second video on digital media explores multiple facets of digital audio signals and how they really behave in the real world.
Demonstrations of sampling, quantization, bit-depth, and dither explore digital audio behaviour on real audio equipment using both modern digital analysis and vintage analog bench equipment, just in case we can't trust those newfangled digital gizmos. You can download the source code for each demo and try it all for yourself!