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by jaydub 3905 days ago
To distribute sound over long distances 'wirelessly' you need to make it loud. That typically means cranking up the power. And ultrasound can be harmful at high power [1].

[1]

"Occupational exposure to ultrasound in excess of 120 dB may lead to hearing loss. Exposure in excess of 155 dB may produce heating effects that are harmful to the human body..."

https://en.wikipedia.org/wiki/Ultrasound

1 comments

uBeam's name is a killing word.