New technique can enable super hearing in humans: Study

New audio technique can track bats in flight and help localize sources of ultrasonic sound. Finland: The researchers from Aalto University in Finland have developed a new technique that enables people to also hear ultrasonic sources that generate sound at frequencies above 20,000 Hz with the simultaneous perception of their direction. The findings of the study are published in Scientific Reports.

Generally, humans can hear and detect sounds that fall in the frequency range of about 20 Hz to 20 kHz.

'In our study, we used bats in their natural habitat as sources of ultrasonic sound. With our new technique, we can now hear the directions-of-arrival of bat sounds, which means we can track bats in flight and hear where they are -- we're essentially giving ourselves super hearing,' says Professor Ville Pulkki from Aalto University.

Small devices have been used before to listen to bats but previous versions haven't allowed listeners to locate the bats, just hear them. With their device the researchers record ultrasound using an array of microphones flush-mounted and uniformly distributed on the surface of a small sphere. After the signal has been pitch-shifted to audible frequencies, the sound is played back on the headphones immediately. Currently, pitch-shifting is performed on a computer, but, in the future, it could be done with electronics attached to the headphones.