Twenty Thousand Hertz is a great podcast that explores sound, in all the ways it manifests. Case in point: "The Deterrent Tone," a recent episode that focuses on Long Range Acoustical Devices, the sound cannons often deployed by police to break up protests. As the episode details, many police departments inherit these devices from the military thanks to the 1033 Program; and those same police departments typically insist that, hey, they're just loud speakers! They're not dangerous at all! There's no way they could be used to abuse and harm the public! It's just noise!
When, in reality, as Twenty Thousand Hertz explains:
Volume is measured in decibels. A normal conversation is about 60 decibels. A loud motorcycle might be around a hundred decibels. An important thing to note here, is that on the decibel scale, the loudness doubles approximately every 10 decibels. So 70 decibels is twice as loud as 60 decibels, 80 decibels is twice as loud as 70, 90 is twice as loud as 80. Any sound over 120 decibels can cause pain and hearing loss.
The smallest LRAD model, the 100X, can go a full twenty decibels higher than that, to 140 decibels. That's as loud as a jet taking off from hundred feet away. The largest LRAD can be as loud as 160 decibels. That's about one thousand and twenty four times as loud as a normal conversation. To put it another way, that's like standing on the edge of the launch pad while the space shuttle takes off.
Not only does that level of sound cause permanent hearing damage, it's also really physically painful. And injuries like this have led to legal action. After suffering permanent hearing damage from LRADs, some people have taken US cities to court. Meanwhile, many police departments argue that LRADs can't be considered weapons.
Spoiler alert: if you're hit by the sonic blast if a highly directional 160 dB frequency, it can permanently fuck up the parts of the inner ear that control your sense of balance. So not only can an LRAD make you deaf, it can also permanently disable your sense of balance, which can also have a long-term impact on your cognitive abilities.
But it's cool! They're "just loud speakers!" The cops said so!
The Deterrent Tone [Twenty Thousand Hertz]