Maskers’ influence on modulation thresholds vanishes beyond 20 dB above their excitation pattern.

Evidence

The influence of partial masking can be summarized as follows: each masker produces an excitation pattern that is described for broad-band noises by main excitations, and for narrow-band noises by slope excitations and main excitations. For signal levels more than 20 dB above this defined excitation pattern of the masker, the masker scarcely influences the thresholds for modulation. — Professor Dr.-Ing. Hugo Fastl, Professor Dr.-Ing. Eberhard, Psychoacoustics- Facts and Models, 1115

Categorization

• XREF: Reinforces excitation-pattern framework connecting masking to loudness and other supra-threshold percepts.
• DEFINE: States main vs. slope excitations distinction for broad vs. narrow-band maskers.