At any given moment, I have at least four synthesis/audio books sitting on my desk for quick reference. Sometimes up to eleven. However, there are only a handful of websites I consider to be true tomes of synthesis knowledge. One of these is Sound On Sound’s Synth Secrets.

Here is a sample of topics you will find there:

Envelopes
Gates
Triggers
Filters
Sample and Hold
Vocoders
Formant Synthesis
Drums
Strings
Organs
and much more…