Pairs of incoherent or coherent noises can be modeled as amplitude modulation

Evidence

It is also possible to interprete this sound sequence as a rectangularly amplitude-modulated white noise. This effect may come even closer to what we call modulation if the two sounds originate from the same noise generator and are therefore coherent. In this case, the equivalence of the sequence of sonnds to that of rectangular amplitude modulation becomes obvious. Thus a suitable model of masking has close relation to a suitable model of just-noticeable variations, as outlined in Sect. 7.5.1. — Professor Dr.-Ing. Hugo Fastl, Professor Dr.-Ing. Eberhard, Psychoacoustics- Facts and Models, 634

Categorization

• DEFINE: Shows how two-noise masking sequences can be reinterpreted as rectangular amplitude modulation, linking masking models to models of just-noticeable variations.
• QUESTION: The ‘sonnds’ typo suggests a proofing error; worth verifying the original text.