ENGLISH
".... a typical person can safely listen to an iPod for 4.6 hours per day
at 70% volume. "
"....knowing the levels one is listening to music at, and for how long
is extremely important. "
From http://www.cbc.ca/health/story/2006/10/19/music-earphones.html
Get the most out of your equipment and enjoy great audio
performance even at safe levels. Our headphones will allow
you to hear more details at lower volume levels than ever before.
Physiology of the Ear and Hearing
For additional information on what loud noises do to your ear and chart reference
http://www.abelard.org/hear/hear.php#loud-music
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