How it feels to get sonic blasted by an LRAD

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Originally published at: How it feels to get sonic blasted by an LRAD | Boing Boing

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I still wish I had one for when the Loud Neighbors crank their stereo late into the night.

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WTF? None of these “facts” about decibel scaling are right.

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So, the Kate Bush solution might be a bit extreme…

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It’s actually worse than that. It’s not a factor of 2, it’s a factor of 10.

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Stolen from the NIOSH sound-level meter app and wikipedia, they suggest a sound level similar to a shotgun blast at 165 dB. Rocket launch is 180 dB. But NIOSH also equate 140 dB to a Jet engine at takeoff. So not completely off?

I don’t know if the power ratio is directly related to how loud something is, but 70 dB has a power ratio ten times that of 60dB. Human perception apparently more closely follows the log intensity. That seems to make intuitive sense - our ability to discern differences at really loud volumes probably falls apart, and hearing damage even over short duration can occur at 120 dB (again, taking this all from wikipedia).

But the take home is that LRAD isn’t just annoying, it can cause physical damage. It is a weapon.

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there’s simple ways to defeat LRAD

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That’s a feature!

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Sound intensity decreases over distance and air density and air turbulence. The Db scales represented mean nothing without context.

Carrier waves may be able to focus the sound but without explaining this it would seem the headline here is just click-bait to pseudoscience.

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Cool, so they won’t object when people make DIY versions?

Probably needs scaling up:
https://www.soundlazer.com/how-to-make-an-lrad-with-arduino/

eta: Even just a mock LRAD would be worth it to watch their reaction when you yank the cover off of it.

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