A collection of examples and sources I use in my teaching.
Amplitude and Ring Modulations
Two of the simplest forms of modulation. A good explanation of amplitude modulation from our friends at Columbia university. Ring modulation using Pd and a Video tutorial on amplitude modulation in Pd.
The German composer Stockhausen used ring modulation for his piece Mantra applying principles of 12-tone composition technique to the relationship between then pianos and the modulators.