Back in the day, the music-dsp list was a hotspot of people designing and implementing their own DSP algorithms for musical purposes.
Olli Niemilato was one of its leaders. He shared knowledge with a sense of humor.
I was delighted to discover his introduction to DSP algorithms in snappy, fun-to-read form.
Additional guides to help you learn DSP from DIYDSP.com:
- Mini DSP FAQ - Equalizers and Crossovers
- Music-DSP FAQ - Directed toward audio plug-ins
- ARRL DSP FAQ - Somewhat about radio