Masking asymmetry grows as masker amplitude increases, favoring upward masking

Evidence

The dependence of masking on the amplitudes of masker and maskee is illustrated in Figure 5.10(b), in which idealized masking level curves are plotted for different amplitude levels of a masker of frequency fmasker. At low amplitude levels, the masking effect tends to be similar for frequencies above and below fmasker. As the amplitude of the masker is raised, the low-masks-high effect increases, and the resulting masking level curve becomes increasingly asymmetric. Thus the masking effect is highly dependent on the amplitude of the masker. — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 1598

Categorization

• XREF: Connects to the reader’s interest in how loud noises deafen the ear — upward spread of masking is why loud sounds obscure higher-pitched detail first.