LRADs and Sound Cannons Are NOT Safe. Here's How To Minimize Their Effects.

It blows my mind how people claim this weapon ‘isn’t that bad’ when people who were exposed to it suffer with permanent hearing damage.

Christ, police shouldn’t be let anywhere near this kind of thing

Hi Benn! Chris from Airwindows. The reason the thin cardboard is working, is because it's rigid mass. It's like watercolor paper: the more metallic the 'rattle' of the paper, the more it will protect you. Foamcore is a little bit softer, and the acoustic foam is softer still. Absorption means nothing here at these amplitudes, but they're so directional that reflection is very effective. Bear in mind that if you are reflecting this attack, any person between you and the attack is getting doubly attacked (no bueno!). Be careful, and be safe! and thank you! <3

The problem are those kind of soundweapons that use your skull as the resonator. It's a lot tougher to protect your skullbones from resonating and spreading the sound to your ears. Even covering your ears still makes you hear it because the sound is literally in your head.

I just want to add some notes about hearing loss that were glossed over in the video (I understand it wasn't the main focus). It's not the perforation/'burst' of your ear drum that's the problem. It's very likely that exposure to this will leave your tympanic membrane undamaged; it's the hair cells of the cochlea in the inner ear that are traumatized by loud noises, and this WILL lead to permanent hearing loss. Also, an eardrum perforation will heal, but the hair cells of the cochlear will not ever recover.

UPDATE: (from someone who invented phase convergence acoustic holography for communications back in '93.) One of the links someone posted included a breakdown of the model 300 which does not appear to be low ultrasound, let alone high ultrasound, but I'm still convinced the top models are. This post only regards high end ultrasound and high ultrasound models, not anything visually resembling megaphones. I've done my best to research and 'theoretically' devise an affordable defense. I have no means of testing if this actually works. I don't recommend finding out. The principle of this design is to scatter high ultrasound enroute before it can phase converge at the target to become audible or low ultrasound. As such it is meant to be held an arms length away. The concept is similar to stealth coatings, except acoustic, not radio. INSTRUCTIONS: Outer layer (preferably black silicon oxide (wet/dry)) facing abrasive side outward of P40 coarse sandpaper for 19khz scattering. Spray that with a very light misting of thinned white glue and coat with a mix of 1.4-5.6 micron diamond or cerium oxide glass polishing powder for 1-4 mhz scattering. (The P40 also phase staggers when the diamond dust is being hit.) Back with layers of P180-P50 wet/dry also facing outwards for 1-4mhz diffraction. Optionally back this with 1/2" squares of aluminum can for general ultrasound reflection reflection and sandpaper vibration resilience. Optionally back this with as close as you can get to 4.25 mm extra thick 'smooth' silicone rubber baking sheet for 19khz 1/4 wave absorption. Finally, optionally mount this all on aluminum street signage for more resilience, impedance, and reflection. * For a quick cheap version, glue a layer of P180 'fine' to the back of your cardboard sign, grit outwards, a lightly tacked layer of P40 'coarse', grit out, on top of that, and turn your sign around to use. Another way of going about this which would disperse even more is to cover a board with acoustic ceiling popcorn (or even actual popcorn), spray that with glue, and coat with a single mixture of all the grits cited. * If you desire a fun art project, look up origami herringbone tessalation on YouTube, and substitute glossy poster paper. The fold dimensions should be decent for devices using only low ultrasound. An aluminum road sign banged to all hell with a variety of ball peen hammers would likely work much better though. * Someone here commented on Tartini Tones aka ring modulation, sum and difference of frequencies. That has existed where low ultrasound 16khz + 16002 hz can create a difference of 2 hz, a beating in your ear. Conceivably it could be used with high ultrasound to create low ultrasound, but it's an obsolete system, not very powerful. A phased convergence sweep could easily deliver 10-100 times as much energy, yet is much tougher to block. It can pass around obstacles in a manner the former can not and meets less air dissipation. I just saw a a breakdown of the 300 which had 2 folded horns. That might be a ring-mod model. * As to why non-glossy side works better, my theory is that glossy merely reflects and transmits through, whereas non-glossy then glossy actually traps resonant sound waves bouncing back through (the paper being the perfect thickness for 1-4mhz waves), and then additionally creates some anti-sound. * I am taking down my explanation. There remains some possibility that I'm actually still quite ahead of the weapon mfgr's and just made a big mistake giving them ideas. However given that G has a product for targeted communications, and that one product i read about elsewhere at least involved an oscillator delayed sweep across the array, I don't think i've handed them any worse than they already know about. Hopefully you read it, plus all the fun stuff you may wish to look into. * 'For some reason' I am not receiving any notifications regarding my posts here, though people were responding to me.

had one of these pointed at me when the police raided my house in 2012. Hearing was never the same. They didn't find shit and dropped all charges.

It makes me so mad you are getting threatened legally over such an informative and well researched video. Thank you for spreading this news and putting your ears on the line to test these devices for the sake of science!

Thank you so much to you and your wife for creating this video showing that these weapons exist and cause pain. Too often people stalked and assaulted with these weapons are labeled paranoid and delusional when seeking help in stopping these attacks. Some folks are definitely more humane than others, and you and yours are the top!

I have a friend who works in Neuroscience, and they've been experimenting with using ultrasonic frequencies "lasered" at different brain structures, and have induced both temporary and permanent/semipermanent alterations to neural structures and cognitive processes. Like relieving pain, inducing euphoria, feelings of religious revelation, fear and revulsion, dyskenesia...its not just hearing that can be damaged or altered by "sound". These devices are much different than the police variety, but give credence to the idea that in music certain tones or sounds can elicit psychogical changes that are directly neurological in nature and not just based on a cultural bias as to what sounds sad or happy or dramatic et al.

These can operate at 160dB? Are you sure that's right? This is totally a weapon if that's the case. For those who don't fully understand how the decibel system works, it's exponential. Benn tested it at 80dB. 80dB to 160dB is 10,000 times louder!

I'll never understand the logic of thinking this is OK to use on citizens. if you support using it then you're also placing a target on your back when your political enemy gets a hand on it too. No one benefits from this aside from the companies who make them.

Not “non-lethal” but “less-than-lethal” which sounds a helluva lot less committed to the concept,

I have heard that thing in Phoenix and did not know it could destroy you like this. I am sending your video to *everybody*. Thank you for saving a lot of people.

Hi there, the paper probably works because of how its made. All of the other materials you mentioned have a regular recurring structure: fabrics have weaves, foams have a regular plastic structure, metals and "plastic" materials have to line up in order for them to have structural integrity. Paper (and paper-adjacent materials), get their strength from the irregularity of the wood fibers that make it. On an industrial scale, it does have sort of a grain (you can tear it more easily one direction than another) but over-all, paper looks really irregular under a microscope. The fibers probably absorb some of the frequency, reflect, and refract some of it. The rattling (mentioned in prior posts) in the paper is called sizing (like the stuff in starchy shirts). The sizing in industrially made paper tends to be alum and rosin. The "rattlier" the paper, the more sizing is in it. This could be another thing to refract the frequency because its just additional "stuff" in the paper matrix. Lastly, the shininess on paper tends to be kaolin clay, the main ingredient in porcelain china. Glossy mags like to use it because you can use a really thin coat and get it super shiny. What else is porcelain used for? Insulators, because it is really effective at absorbing and diffusing energy because of its super-fine particle structure. So your glossy cardboard is effective because of the thick and irregular structure of the cardboard, probably having a built in sizing element, and a tiny (but still important) coating of clay. If that logic holds, MDF (medium density fiberboard, or low if available), cork, thick handmade papers, thick long-fiber tissue (Japanese tissue) or other materials with an inherently irregular structure like that might work. Also, the Lab Safety Czar in me asks that you find a sound measuring sensor that isn't you, should you continue to do this sort of research. Be safe!

It just hit me about 6 hours later. The take away might just be to DESIGN YOUR PROTEST SIGN with the possibility that you can use it to shield you temporarily, and give you enough time to regroup.Those are just my thoughts. Shreddward sent me.

Had no intention of learning about LRADS today, but glad I did.

Make your protester signs out of large pieces of glossy paper

If you want some help researching sound lasers let me know, happy to lend whatever help

LRADs (Long Range Audio Devices) must be banned for use against humans FOR ANY PURPOSE, whether military or civilian or anything in between or beyond. Just like the ban on anti-personnel land mines.