When I was a grad student decades ago, I worked at a research center aimed at the study of noise-induced hearing loss. Temporary threshold shift (TTS) was a hot topic. Rock concerts were in vogue, and lots of folks were concerned about whether they were injurious to hearing. The answer is they can be depending on where you are and for how long. If you measure carefully enough, you'll discover that even low levels of sound can cause TTS, but recovery is rapid. Buy a Radio Shack sound level meter. I'd use slow trajectory, because the auditory system integrates sound. At this point, I'm not sure what the value of a hearing test could be, but I would avoid prolonged exposure to what seem to you as loud music.
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