That is the idea behind "audio enclaves"—a unique sound technology made by a couple of researchers from Penn State University. In a nutshell, special projectors beam self-bending ultrasonic ...

Ultrasonic pest repellents, such as Haycone Indoor Ultrasonic Repellent from Amazon emit sound waves at frequencies higher than what humans can hear, typically above 20 kHz. According to Nicole ...

Ultrasonic pest repellers, once plugged into an electrical outlet, operate by emitting short wavelength, high-frequency sound ...