It’s well known that many animals are particularly sensitive to high-frequency sounds that humans can’t hear. Many commercial pest repellers based on this principle are available, most of them ...

For years ultrasonics meant something only to dogs and other subhuman creatures. One of the few uses of ultra-high sound waves was in whistles, too high-pitched for human ears, to call pets. Today ...

BOSTON (AP) — Researchers at the University of Massachusetts Amherst are trying to create an ultrasonic whistle to keep bats away from wind-turbine blades. The scientists want to reduce the number of ...

These whistles show the divide between what people think is silence and what dogs truly hear. 5. Electronics With Hidden Sounds Many household gadgets quietly hum at ultrasonic frequencies. TVs, ...