Turn That Noise Down!

040525As a parent I always told my kids that loud rock music would damage their hearing.  But as a scientist I was on flimsy ground.

I ignored experiments that compared hearing loss in people who regularly attended rock concerts with control groups who didn’t listen to this kind of loud music.  An insignificant hearing loss of 2-3 decibels was found, even though the sound levels at rock concerts was well above a hundred decibels.  On the other hand factory workers exposed to this level of sound showed considerable hearing damage.

Our ears do not register very short duration sound peaks.  The brain samples a sound before deciding what to receive.  Because of this reaction time, short peaks of sound may pass through the ear without invoking the normal protective mechanism.

At sound levels above eighty decibels, the little bones that transmit vibrations from the eardrum to the inner ear stiffen and transmit sound less effectively.  What damages our hearing is not the average sound, but the peaks.  Factory noise has a lot of peaks, which although not registered by the brain, can damage the hearing by destroying hair cells in the cochlea.  Since the sound at rock concerts comes through loud speakers the short sound peaks are limited.

So next time, whatever your opinion of the music, you should admit it probably won’t seriously damage your hearing.