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

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!

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.

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.

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.

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.

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!

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 RU-vid, 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.

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!

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.

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.

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.

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.

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

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 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.

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

Make your protester signs out of large pieces of glossy paper

It's absurd that you needed to make this. This is mad.

There is no possible excuse for police to use this on a protest. It's an admission of guilt when they use weapons against peaceful protestors using a few people who may have done some minor infractions as an excuse to attack working class 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!

LRAD's are also being used in Orlando, and Orlando PD has released a statement saying that they are used to relay announcements over long ranges. This is false. The models used by police departments are the same ones that were ruled as being "excessive force". The model in the case against the NYPD using them, where the ruling was made, was the 100x. The one currently in use by the Orlando PD, and likely others, is the 500x. It is made by a company called Genesys, and the use of LRAD's in overseas combat has already been banned. Also, they can effectively be disabled by perforations in general EDIT: Actually i'm pretty sure any perforations at all would disable them. Also, i forgot to mention, the 500x is about 3x as effective as the 100x, the model that was used when these devices were ruled to be excessive force.

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

Thank you for your video. A lawsuit is just proof that these things are dangerous and they have something to hide.

Benn: "If you have some sort of particular political criticism to this video and it makes you want to unsubscribe to my channel, then by all means unsubscribe." Me: *slams that subscribe button*

At least three decades ago I remember Anti Nuclear War - Peace Protestors reporting head pains and feeling Heat in their heads during certain Actions. Some monitoring followed these reports and results suggested beamed micro-waves were being projected. People literally became Hot-Headed and less inclined to restrict themselves to Peaceful protest. I wonder what refinements of That technology have been made in the intervening decades? The 'non-lethal' market has been flourishing apace.

Benn I've watched a lot of your videos on modular synthesis and other sound design topics. Totally awesome how you took your knowledge and used it for much needed activism and protection of the people. Mad props!!!

You sir, are so badass for making this video. I’ve been researching this and am no longer that worried anymore!

Is a great, but painfully and risky, demonstration you made. The 15k sound may be worse because is near the cochlea natural frequency (but usually is nearer 10k, but also could that the HS modulation could hit certain harmonics, thou. Intermodulation can give weird peaks sometimes). The higher pitch couldn't say why, but I imagine on how our ears tend more to take HF as positional information, and our brain, when something just doesn't feel right tend to get confused, like having motion when you don't have a point of reference, and also the opposite. Thank you for making this video and putting them as they are: dangerous to everyone. Is the equivalent of pointing lasers to people's eyes, in my ears. Hearing loss is not taken as seriously as it should. Also, in safety terms, 80dB should be safe in 8 hours exposures, but is taken in A ponderation, and also considers that the overall noise is centered on 1K (hence the A ponderation). HF pack quite more energy, and could be harmful even as low as 74 dB, AFAIK

Hi benn, amazing video and very needed at this time! I am physics graduate and I think I can explain why the paper works and the foam doesn't. The purpose of acoustic foam is to ABSORB sound, this means that while a sound wave passes through it, its amplitude gets decreased (because foam is a very dispersive material, meaning it has a bunch of holes in which sounds bounce around a lot), this works really well for lower volume outputs, but LRADs are VERY loud as you explained, therefore the foam does reduce a bit the volume but not much else. The paper on the other hand is solid and smooth, therefore it bounces the sound wave (or at least a bug chunk of it) right back! Exactly like if you were in a big hall with smooth walls, there is a bunch of reverberation, the paper acts like a "mirror" for sound waves!

Thank you for making this video. You’re going to save a lot of peoples’ hearing with this information.

I never thought background noise would have a regular enough waveform to allow for inversion cancellation. That demonstration blew my mind.

hey, thank you. I'm sharing this widely with friends in LA. I appreciate you getting this to us so much.

Aren't we the people they work for ? I hope this is used so it can become illegal for the police to use.

Hi, thanks so much for doing this. I have some on-the-ground requests. Sorry if this seems demanding, its just that you understand and have access to this stuff and most of us don't: 1. For access reasons, can you make a >5 minute version of this, and have written captions like "FOAM DOES NOT WORK," "THIN PAPER WORKS WELL AT 15K HZ" etc. A lot of rumors are flying, some based on this video, some that are misinterpretations of what you've presented here. This info is awesome and its great to watch yall nerd out in comments, but a lot of us just need quick info and not a technical explanation of how the LRAD works. 2. From the video, it SEEMS like commonly used protest sign materials would work well. The kind of paper you used successfully isn't as easy to buy especially right now, but cardboard packaging is everywhere. There's also some talk online about making corner reflectors (twitter.com/LikeClocktwerk/status/1268794692855951360), maybe out of cardboard. Maybe that's dumb, I'm not a sound tech so I don't know. Can you test out the following, flat, and arranged as corner reflectors (which one could pre-cut): *glossy food packaging cardboard (eg. cereal and beer boxes) *corrugated fiberboard (regular moving-box cardboard. w/ wavy layer encased in two flat layers) *waxed cardboard (used for produce, should be some behind any food store) *regular cardboard w/ mylar pasted on one side, if that seems relevant 3. If you or anyone with the technical ability is up to it, it would be a good idea to solicit and compile on-the-ground experiences trying these different methods of deflecting LRADs. 4. Can't locate the comment but someone said that the ones they're using are at 22,000 hz or something, thoughts? 5. In the video you say the matte side is more effective than the glossy, but the summary says the opposite. Just tryin to clarify. Thank you so much!

Wait, holy shit you're Benn Jordan??!?!? I LOVE your work. I've always wanted to see you live. If touring ever happens again, please come to SLC. I would love to meet you. I've been listening to your stuff since Red Extension of Me and the SICKEST bass line I have ever heard on An External Frost. You are incredible. Keep up everything you do.

Thank you for your support and service.

Thank you so much for this! I had no idea that these were a thing and it’s really kind of you to help inform everyone :)

I read somewhere a Corner reflector could redirect the sounds back at the operator. It wouldn't protect you but it would definitely make the cops taste their own medicine a little. I'd be interested in someone testing the principle.

Frequency resonating the different materials absorbing or deflecting. Like the microwave towers that are just big metal panels. Tuned to the frequency to reflect the signal from mountain top to the next mountain top. (The passive metal panels you once used to see)

I just realized that RU-vid constantly recommending me your channel was without me having subscribed, so I guess this video earned my subscription in a sense. really the subscriptions because of all the awesome production tips but not getting injured during activism tips are also extremely great and good

Been listening to your music since the 2000s. Having you do these youtube videos is amazing. You definitely cover a range of topics and i really appreciate your content

Benn: Try sandpaper of different grits (and please find my other posts describing how acoustic holography works). A course 36 grit is likely ideal (rough guess), but it would depend on the mhz of the transducers used. Multiple layers should work even better. Tightly wrinkled then flattened aluminum foil might help. Silicone rubber sheets at 1/4 wavelength thickness should help. However keep in mind we are trying to block two different frequencies, the constituent 1-4mhz and the phase convergent 19khz. If you really wanted go all out, two top layers of 36 grit sandpaper, a layer of aluminum squares in any size from 1/4" to 1" at 0.025-0.1 mm thick (depending on 1-4 mhz device), a silicone rubber sheet preferably 4.25 mm thick (for the low ultrasound 1/4 wave, and finally a thick say 3mm aluminum street sign board. You can not remove sound, only transduce it to other frequencies or energy types. Come to think of it i once designed a car muffler material which had a thin sheet of spring metal cut into a grid of v-cuts to create harmonica reeds. It's purpose was to convert audible frequency exhaust noise into ultrasound frequency people couldn't hear with as little impedance as possible. Ok, just read about the gag order and got it now. I have a lot to say towards your defense in a comment there as well.

Thank you for this. Pigs hit my community with a sound cannon tonight and it sucked shit. I had ear plugs in a motorcycle helmet and I still had to give up ground. We are spreading this video around now to help protect ourselves. Thank you.

This and your vinyl degassing videos are fascinating! So much potential for new scientific research. Also, glad to see you helping spread some safety news for protestors!!

Make your protest signs accordingly. They can be used as your anti-sonic shield if need be.

I'm a new subscriber. Great content you've got here. Very informative and entertaining. Also, great idea for a video. Doesn't matter what your political party is, if people have a problem with information then they have an agenda. This is extremely helpful information for anyone. Keep up the great work and I wish you the best.

Thank you both for this video, those headaches are a small price for this knowledge.

upset I didn't see this last year, but glad the info is out there.

right on brother. power to the people

I saw a video about how to stay away from LRADS on tik tok but they didn’t go into much detail. Thank you for teaching me something new and testing it on your self to shoe us how these machines work !!!

Thank you for getting to the conclusion right off the bat. Appreciated. Have you tried a umbrella open and handle towards the source? Wondering if that disperses in a similar way.

Your efforts are appreciated 🙏 thank you so much for this information

Hey Ben, thank you for making this. Greetings from Englewood.

Absorption coefficients are a rating of the percentage of sound that will reflect after hitting something like the foam. It gives no account for what will before hand penetrate the given material. The equation for this likely means that even at 80 db a great deal of 2.5-3.5 kHz will pass right through. This is why putting up foam in a studio does almost nothing for acoustic isolation. You need mass. You're best results here were because of surface density which is the best indicator for reflection. Thank you Benn!

Thanks for keeping this video up and for taking the risks to inform us!

Hey Brother hey thankful for your witness. Thankyou 👍

Thank you so much for making this video, I really appreciate what you're doing

I got linked here from a message board that''s talking about current events and I'm all like...damn you look familiar and then it hit me...YOU'RE THE FLASHBULB!

You’re awesome, thanks for this Benn. Quality was fine.

I'm a recent follower of your work coming to this video much after the immediate relevance period. Great content coming from an even better ideological position.

Super cool of you to post this. When the BLM protests were happening my room mate told me about how the police were using Sonic Weapons, and when he explained them to me I was terrified. What a horrifying version of warfare, and it definitely made me much more hesitant to join the protests.

Great video Ben, thank you for your efforts and research

There's alot I want to say but in short Thank You, for the info and for the support ✊❤✌

With the glossy paper would layering the paper loosely, like stapling two of the four edges together, work better?

Glad you're raising awareness of these. I knew about them being used by special ops, but didn't realise they're being used on the public. If police have them, it won't be long before criminals get hold of them. The first time I ever heard of LRADs were to deter pirates off the Somalian coast - that's a use case I could get behind, given that crew on container ships aren't allowed to use firearms to defend themselves against being boarded by armed pirates. But this is something else, a weapon that invisibly maims your main sense permanently - that's truly scary.

Thank you. I didn't hear Seattle listed, but I wouldn't rule out our cops starting to use LRADs in the near future.

Thank you for doing the work and helping people be safe at protests

‼️‼️ Perfect timing ‼️‼️ 🙏❤️ Love from Scotland ❤️🙏

"shoot it at the geese" Finally, potentially an effective weapon against the true enemy of mankind. In all seriousness, this is inhumane, regardless of your opinions on the protests. If you cheer for this to be used today, I hope you cheer when it gets used on you.

Omg thank you for doing good work and for you and your wife suffering a headache to help protect others 🖤

Great vid, hope you and your wife are ok. Stay well, stay safe. 👏👏👏👏👏

You're such a hero for posting this. Much be how they do that direct to skull thing

Super informative man!!!! Thank you for your service!

Thanks for all your videos, such a great channel. A bit unrelated but any chance you can make a video of you creating one of those glitchy drum beats you do so well? I know you’ve mentioned before that it’s essentially just takes a lot of time and it’s boring work but I’d sure love to see it, and I bet others would too!

We need this more than ever as its being used in my city while i watch remotely.

Just a thought: would a satellite dish possibly reflect the incoming "beam" of sound? The focal point would likely be too near to be as effective on the operators, but it could reflect some of the noise back (I have minimal acoustics knowledge, just some stupid ideas).

Awesomely unexpected video. I'm curious if the posterboard would be as effective if it had something reinforcing the sides to make it more useful as a sign. Similarly, plastic or vinyl sheeting on a rectangular lattice of dowels or something. Very interesting!

Thank you for your service. You're doing good work.

This is a true PSA. Good on you Benn.

I subscribed explicitly because this was great info to have.

Fuck yes dude! You're Fing awesome. Was just thinking about all this over the last few days!! Are there any videos of these being used? I've only seen a small snippet from NYC a few years ago. Also, (haven't finished video yet) do you cover infrasonic?

thanks for pumping out the video and spitting the facts quick

Thanks for doing this Benn...

I wasn't subbed, now I am.

Currently struggling with Havana syndrome v2k the people doing this to me are John Johnson Lisa Johnson Mallory Johnson they live in socal around Murrieta and Anaheim

been watching your Spotify videos.. but this one right here.. scary-fascinating

I can't help but wonder how effective a metal mixing bowl, or other items with a parabolic shape, would be at reflecting this bad acoustic juju back...

you are AMAZING thank you for this vid especially making it relevant to these times!!!!

i could feel pressure in my head during the 19khz testing and afterwards. same kind of tension headache as you and your wife had there i think. my hearing is extra sensitive so that might have affected things, but still. god i dont want to know how awful this could feel real time

THANK YOU for this valuable video!!!!

Good info, timely. Thanks!

Thank you for sharing this information 🙏

Thank you for your services.

It's mazing the amount of research we as humans put in to hurting one another. Bill P

Thank you so much! I will share with everyone!!

Thank you for making this! Subbed!

This is really important info, thank you.

Wow, I never knew that you could invert back ground noise to remove back ground noise like that. Very cool. When I took a film making class they did tell us to capture some silent background noise on set, but they only told us it was useful for masking edits in the audio. Very cool little extra tid bit. Also, important video. I had no idea they were using stuff like this as well, before watching this.

What if all frontline protesters tried to reflect the wave back would that be effective? Strength in numbers?? Agghh I hate this thing