Reduced BMLD stems from masking effects, not from signal frequency or masker level

Evidence

These additional data show very clearly that the reduction of BMLD is neither a result of changing signal frequency nor a result of changing the effective level of the masker. — Professor Dr.-Ing. Hugo Fastl, Professor Dr.-Ing. Eberhard, Psychoacoustics- Facts and Models, 1666

Categorization

• QUESTION: If it is the masking itself that shrinks BMLD, what exactly about the masking mechanism causes the degradation? Worth pinning down the mechanism.