sound (and mechanical heat, for that matter) is nothing more or less than aggregate motion in particulate media. it is a known fact, testable, demonstrable, that intersecting sound waves of the same frequency and phase will amplify each other in a harmonic at the point of intersection, whereas intersecting sound waves of the same frequency but opposite phase will cancel each other. I believe something similar is true of radiant energy (light, infrared heat, radio, etc... but that is outside of my competence)
In a large enough set, of high enough density, with a finite range of possible energy signatures, it is inevitable that random sources will produce harmonics and cancellations, which will in turn cause organization in what was previously a uniform distribution.
Any large enough random system will contain all possible patterns.