(Sound effect: hip hop scratch) Nipping It in the Bud.
I'm Bob Karson with the discovery files -- new advances in science and engineering from the National Science Foundation.
(Sound effect: hard rock) If you're listening to this with earbuds you could experience "listener fatigue." And it has little to do with me, the subject matter or this music. It's your ears just doing their job. Engineers at Colorado's Asius Technologies have the cause and the cure for this condition.
Their research deals with systems that seal the ear canal such as in-ear headphones or hearing aids. They initially found these systems create a highly magnified sound pressure level. And what amounts to a physiological 'catch-22'. You see, your ear has a built-in acoustic reflex that's triggered by high sound pressure levels. Sound gets dampened to protect your inner ear, but that in turn causes you to turn the device up louder. The more you pump it up, the more you subject your eardrum to excessive shaking.
Once the team understood the way the process works, they set out to develop a system that would break the cycle. Their solution: build a "second" eardrum a synthetic membrane attached to the tip of any in-ear device to take the brunt of the pounding. Eardrum protected no acoustic reflex and lower volumes sound louder.
The accurate, non-fatiguing sound provided by this new technology can be retrofitted on existing devices. It could mean a safer, richer sound for those wearing hearing aids (Sound effect: loud music) and less need to "crank it up" (Sound effect: loud music abruptly cuts) for the rest of us.
"The Discovery Files" covers projects funded by the government's National Science Foundation. Federally sponsored research -- brought to you, by you! Learn more at nsf.gov or on our podcast.