> but since they can only be higher frequencies than the original
That's incorrect, distortion products spread both upwards and downwards in frequency. The easiest example to analyze is x^2, which corresponds to the spectrum convoluted with itself. From there it's easy to expand into polynomials.
Anyway, what you're describing is pretty much a single step in a standard blue noise algo iteration.
You’re right. While a pure tone can only have higher harmonics when distorted, multiple tones can produce the difference frequency. And noise has every tone.
That's incorrect, distortion products spread both upwards and downwards in frequency. The easiest example to analyze is x^2, which corresponds to the spectrum convoluted with itself. From there it's easy to expand into polynomials.
Anyway, what you're describing is pretty much a single step in a standard blue noise algo iteration.