When it comes to the health of your hearing, how much noise is too much noise? Sometimes it's hard to know.
A pair of intelligent earplugs, however, can make that determination for you. In quiet environments, the Quietpro+ earplugs "open" so wearers can hear normally. When the noise level rises, the 'plugs automatically filter out the clamor while continuing to let speech through.
The earplugs, from Norwegian company Nacre, are already in use by the U.S. Army, special operations forces, Navy, and Marines, as well as NATO forces (the Air Force has its own teaming with international energy company Statoil and Sintef, an independent Scandinavian research organization, to create a next-generation version for use in the offshore oil and gas industries.). Now Nacre is
Each earpiece of the Quietpro+ 'plugs incorporates a mini-loudspeaker and an internal and external microphone. The headset attaches to a small, battery-operated control unit, carried by the user, that contains a digital sound processor. The circuitry monitors the sound waves sample by sample, at a speed of 64,000 samples per second.
When noise rises above a predefined threshold determined to lead to hearing damage, the system self-adjusts. Users still hear a gunshot, say, but at a nonthreatening level, while the surrounding sound (echoes, for example, and communication from people in the area) is amplified normally in full stereo. The control unit can also connect to a radio or intercom via cable.
For now at least, the adaptive earplugs--which are lightweight, watertight, and compatible with all kinds of helmets, gas masks, and other protective headgear--remain in the purview of those in combat or other super-high-noise environments. But those who live next to fire stations or sit near co-workers prone to shouting fits probably will look forward to the day when they're available to the noise-polluted masses.