Level discrimination for broadband noise is level-independent above 40 dB sound pressure

Evidence

Changing from tones to broad-band noises affects the dependence of JNDL on sound pressure level. As indicated in Fig. 7.7, the level dependence disappears almost completely for white noise in the sound pressure level range above 40 dB. If white noise is limited by a low-pass filter so that the upper slope of masking with its level dependence can be seen, the level dependence becomes noticeable again, as indicated by open circles connected by broken lines. The size of JNDL around 60 dB sound pressure level is about 0.5 dB for most broad-band noises. — Professor Dr.-Ing. Hugo Fastl, Professor Dr.-Ing. Eberhard, Psychoacoustics- Facts and Models, 1049