When predicting the overall loudness of time-varying sounds, it is necessary to use a function which calculates an overall value based on instantaneous loudness. Although N5 and LL(P) correlate for many sounds, their concepts are rather different. N5 is the loudness which is exceeded in five percent of the time, thus it is an ordinal value. LL(P) is the energetic mean of all instantaneous loudness values. For the present set of experiments, sounds with orthogonal conditions were chosen. This means they vary in N5 in a dynamic range of about 30 phon but have constant loudness according to LL(P) or vice versa. Participants judged the overall and instantaneous loudness of the sounds with ten seconds duration by magnitude estimation using line length and continuous judgment. The results show that LL(P) has some advantages compared to N5. In contrast to N5, it correlates highly with the overall loudness for the present set of stimuli.
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