Someone asked somewhat recently about visualizing analytic signals in 3D (https://news.ycombinator.com/item?id=28633829). This is my video, with 3D animation, summarizing the FFT and analytic signals, plus a review of digital sampling.

The submitted link is for a blog post about the video which includes a video transcript (repeated for reference: https://blog.mikebourgeous.com/2021/10/04/fast-fourier-trans...)

Here's a direct link to the video: https://www.youtube.com/watch?v=iyjIVSnrPSo

I've opened the Ruby code building blocks I use to produce these visualizations (which are not open): https://github.com/mike-bourgeous/mb-sound