GS PAPER III: Science and Technology- developments and their applications and effects in everyday life.

Context: New audio technique allows hearing ultrasonic sources.

• The spherical array has 6 microphones sensitive to ultrasound.
• The ultrasounds are played back to the headphones so that the listener can detect the direction of their source correctly.
• Humans, have a limited range of hearing and can perceive only certain sound frequencies – generally stated to lie between 20 Hz and 20,000 Hz.
• A new audio technique, developed by researchers at Aalto University, Finland, will now allow people to hear ultrasonic sources that generate sounds of frequencies over 20,000 Hz.
• The technique would also allow for perception of the direction from which the sound is coming.

Applications of this device:

Listening of bats:

• Bats in their natural habitats were employed as the source of ultrasonic sound in this study.
• Using their technique, the researchers were able to hear the direction of arrival of bat sounds, effectively allowing them to track the bats in flight as well as hear them.

Detect pipe leaks

• Minor pipe leaks and sometimes even damaged electrical equipment produce ultrasonic sounds, this device would enable quickly detecting the location of such faulty equipment, saving valuable time.

https://www.thehindu.com/sci-tech/hearing-beyond-the-normal-range/article34898897.ece

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