I’ve just come across two outstanding tutorial videos over on xiph.org – an open-source organisation dedicated to developing multimedia protocols and tools. So, the first one covers the fundamental principles of digital sampling for audio and video, and discusses sampling rates, bit depth and lots of other fun stuff – if you’ve ever wondered what a 16-bit, 128kbps mp3 is, this is for you.
The second one focusses on audio and gets on to some more advanced topics, about how audio behaves in the real world.
They’re both fairly long (30 mins and 23 mins respectively) but well worth watching. If you’re just getting started with digital audio and/or video editing and production, these could be really useful.