Actual sound pressure levels at pop-music concerts Historical review from the 1920s to the present

Most concert halls are equipped with fine sound reproduction systems for public broadcast of speech and reinforcement of musical sound. The “power” of such sound reproduction systems has been increasing in Japan since the middle 1960s. Presently, it is not unusual at all to encounter sound pressure levels higher than 120 dB at pop-music concerts. This arouses concern about severe effects on hearing ability, particularly for young listeners. In fact, at such concerts, some audiences claim temporary threshold shift (TTS) and tinnitus. This report reviews actual sound pressure levels encountered at pop-music concerts in Japan since the 1970s including a contemporary example from 2003. Then, we speculate about possible reasons why music producers and musicians have steadily increased sound pressure levels of reproduced sound.