Quietnet: near-ultrasonic messaging service sends chat by chirps


If it uses near-ultrasonic chirps, shouldn’t it be called ‘painfully loud net’?

A lot of common things, from fluorescent lights, to car brakes, to computers, to incapacitating safety systems, can hurt people with sensory sensitivities. I’m sick of being in agony because someone thought bright lights were better, flashing lights were an important safety feature, high-pitched beeps were better, and ‘near-ultrasound’ squeals wouldn’t bother anyone, let alone incapacitate someone across from the construction site, in too much pain to stand up let alone walk away from the beeps and the squeals.

So this sounds like another example of either ignoring or hating people with sensory sensitivities.

I know that it could be quiet for some people, but not for the rest of us. I had to bring an old computer in for repairs because of painfully loud processor noise. A few days later, they called to say it was repaired. I came to the repair place and it had the same painfully loud processor noise. After asking, it turned out that the repair guy couldn’t hear the problem so decided there was no problem. I then sent the old computer back to the manufacturer for repairs. A few weeks later, I got the call that it had been repaired. I came to the repair place and it still had the same painfully loud processor noise. After someone checked it out with an audiometer, I was able to turn it in, but I have had ergo and noise problems with the new one…


While not in exactly the same vein I feel for your auditory issues. Due to some ocular issues I am able to see “blinking/flicker” well into the 150hz range. This means things like LED Christmas lights and most newer LED taillights on cars irritate me to no end.


Damn. I don’t have trouble with leds, I’d actually suggested that they were better than the strobe from fluorescents. thanks for the heads-up.

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I wonder if tying this to random data to produce ultrasonic noise would be an effective jamming device against anecdotes about air-gapped malware communicating through ultrasound networking protocols.

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Don’t politicians use something like this to distribute their talking points to their base already?


I think my hearing has gotten a bit less sensitive over the past few years, but I used to hate going to my local supermarket. Every time the staff used their devices to contact each other I would hear a loud, high pitched sound that quickly gave me a headache but didn’t seem to affect anyone else. I’d also hear TVs that were on standby from outside the room. There seems to be a lot of technology that’s designed without considering the effects they might have on sensitive ears, so I always wondered whether this could be a reason for some kids or animals acting out in supermarkets and other places.


It’s well-established, but it’s easier for people who can’t hear the sounds, and can’t accept that other people can, to blame the kids, and blame autism if they’re autistic, than to consider the built environment.


Can we put these messages on vinyl to ensure the highest possible fidelity?


Seems a market exists for people with sensitivity issues to bright lights and sounds… but no good solutions.

Someone will probably become a millionaire in a month for kickstarting some solutions to this.

Fashionable noise cancelling ear (or near ear) wear to prevent annoying repetitive noises, loud noises, high frequency noises… etc…

Same with glasses that could do the same.

They don’t even have to work… the beauty of Kickstarter is it just has to be promising, presented professionally (but with enough indie cred), and within the realm of possibility.

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They should be completely strobe-less if powered over actual direct current. That being said, I bet that most Christmas tree lights have minimal circuitry to convert the AC from the mains. Strobing on headlights probably comes from the alternator.

Yes it would eat its lunch.

It’s generallly PWM control to dim the LED. It basically flashes on and off quickly to simulate dimming.

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Dimmable Christmas tree lights?

And ironically a nickel capacitor would fix most issues. The older Caddy DTS had an excellent two step LED configuration, no PWM needed.

I wonder if you could use this to detect badBIOS-like malware?


Interesting that it uses FSK (frequency shift, like RTTY) for encoding the bits but it uses the ham radio PSK31 modulation method’s Huffman variable bit-length encoding scheme for speed. PSK would normally use phase shift to signal bit transitions, but probably wasn’t used here by Kate because the airgap doesn’t do a good job on preserving phase, at least in my experience. Using FFT to decode the FSK is one approach, but a pair of matched digital filters would likely give better performance at lower CPU cost.

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So this sounds like another example of either ignoring or hating people with sensory sensitivities.

I’m hurt that you would accuse me of this. I certainly don’t hate people with sensory sensitivities. Actually I’m pretty sensitive to noise myself and carry a pair of these earplugs [not an affiliate link] for when I’m out and about and want things to be quieter.

This was a toy project I did to figure out how to do something I didn’t know how to do, and isn’t something I’ve ever promoted. If someone is causing you to experience unpleasant sensations please let them know, maybe even warn them in advance that you have this sensitivity if you feel comfortable with that.

I know that it could be quiet for some people, but not for the rest of us.

In my testing it’s actually silent for the vast majority of people. Which is consistent with the references I’ve read about human hearing topping off at ~20kHz and dropping with age.


Install the software, see how it goes.

If it’s purely personal, that’s one thing… but there are so many other commonly-used technologies and safety/incapacitation features and so on that give off high-pitched pain, that when yet another of these things comes into common use, it will be a life-destroying level of awful.