Improving Hearing Aids

Even though other noises can reach up to 20kHz (kilohertz) in range, most hearing aids only pick up sounds up to 5-6kHz. That leaves out some of the higher frequencies used in speech. Cut off the higher frequencies, words like "finding" and "signing" are nearly identical. Phones compound the problem by compressing the range further. Brian Moore of the University of Cambridge say they've come up with a way to boost the upper range of hearing aids. Find out more at the Economist here.