Shorter tone bursts drastically worsen level discrimination while longer ones do not help

Evidence

For measuring just-noticeable differences, a pause is needed between the sounds to be compared. For pause durations ranging between 0.1 and 2 s, the results are independent of the duration of the pause. The data given in Figs. 7.4 and 7.5 were obtained with a pause of 200 ms, which is still within the range of independence but short enough to make it a very easy task for the subject. Besides the pause separating the two sounds to be compared, the duration of the sounds influences the size of the just-noticeable difference in level. With the level difference measured at 200 ms used as a reference, the dependence of just-noticeable level differences on tone-burst duration is indicated in Fig. 7.6. JNDL increases by almost a factor of 5 for a reduction from 200 to 2 ms. This corresponds to a slope of about ~6 dB per decade within this range. For a duration longer than 200 ms the JNDL does not decrease much. — Professor Dr.-Ing. Hugo Fastl, Professor Dr.-Ing. Eberhard, Psychoacoustics- Facts and Models, 1044