ciscoeuk":5jgyeu4z said:
the best way to cancel hi noise is with noise like music.
I may be misunderstanding, but if you're using music to drown out the sound, you really, really don't want to be doing that with modern digitaly recorded music*.
I couldn't find the paper I was looking for (around 1980-ish), but this one:
http://www.ncbi.nlm.nih.gov/pubmed/10465907 pretty much covers the same ground.
Basically, what it means is, if you listen to digital drum tracks on headphones, you run the risk of notching your hearing at the exact points used most for recognising speech. Impulse noise (percussion, shooting, etc.) is the most quickly damaging, but planers, routers, saws, etc. also do harm. Hearing damage from environmental factors (loud noise) is almost always permanent.
The audio industry picked up on this at the start of digits, which is why professional headphones often nowadays have sound limiters built in. There is talk amongst those in the know, of a "deaf generation" in 10-20 years' time, when the effects of over-use of iPods etc., kicks in and that generation become forty-somethings.
The best thing, for your hearing's long-term health, is good ear defenders together with well-fitting soft earplugs.
I'm not trying to put you down at all, but I used to make my living with my ears, so I had to know the risks.
Cheers,
E.
*digital percussion can be louder than it appears to the brain, which is one factor in how the ear gets quickly damaged (likewise with target shooting and drop forges). Audio from analogue tape doesn't trick the ear in the same way, so doesn't tend to be as harmful.