Tone-burst loudness rises 10 phon per tenfold duration up to 100 ms, then plateaus.

Evidence

A factor of two in loudness corresponds to a loudness level difference of 10 phon. Therefore, it may be interesting to see the results of Fig. 8.12 with a loudness level ordinat.e. This transformation leads to Fig. 8.13, which indicat.es that. loudness level decreases by 10 phon if the duration is reduced by a factor of 10. The broken rising line indicat.es this approximation, which approaches the steady-state condition (the horizontal) at a duration of 100 ms. Similar result.s have been produced at several other frequencies and lead to the same dependence, which can be expressed most easily for durations below 100 ms by the following approximation: the loudness level increases for 10 phon for each 10-fold rise of the duration of the t.one burst. Above 100 ms, the loudness level is approximately independent of duration. — Professor Dr.-Ing. Hugo Fastl, Professor Dr.-Ing. Eberhard, Psychoacoustics- Facts and Models, 1233

Categorization

• XREF: Connects to the onset/temporal-integration literatures in psychoacoustics and to how temporal summation of loudness is modeled (e.g., for sound reproduction systems).
• corroborated: 2 independent passages support this claim — Professor Dr.-Ing. Hugo Fastl, Professor Dr.-Ing. Eberhard, Psychoacoustics- Facts and Models, 1233