I don’t think this is even possible. Noise canceling works by creating reverse waves that hit your ears at the same time. You have to be able to calculate how long it will take for those waves to hit each set of ears and be able to direct sound at them.
Right, but the speed of sounds is slow. So things like placing a microphone 6 feet closer to the source allows for much more effective noise cancellation. Current tech in earphones skips that by using past noise as a prediction of future noise, and as a result only works on near constant noise of airplanes and other near constant sources of noise.
> only works on near constant noise of airplanes and other near constant sources of noise.
That is simply not true - at least in my experience with an old model of Sony headphones. It's possible that prediction plays some role, but I bought mine with specific purpose of silencing neighbor's kids.
They work really well with this kind of sporadic, random noise and the difference between turning on active cancellation and just passive attenuation due to ear muffs is very noticeable. I'm talking about low-frequency noises that are mostly transmitted through the vibrations in the walls and floors - feet hitting the floor while running, ball bouncing of the walls and so on.
That's the simple, signal-processing oriented way to noise cancellation.
But what if the software/ai is advanced enough to reproduce a sound, but erase a certain aspect of it? Like how photo editing can edit out an object or background? Then the headphones can use a seal to completely block out all noise, and play only the sounds the user selects!
If we could make a seal that blocks out all noise small (and confortable) enough to fit around a headset, we wouldn't need the whole NC setup.
Earplugs below my bose headset work wonder to block out anything short of cataclysmic, but it's hardly practical. And I can't exactly play music with those on...
It's funny because the best passive noise canceling IEMs are basically ear plugs with drivers in them. Blocks background noise as well as ANC but only weigh a few grams.
I think you have misunderstood the parent comment. The suggestion isn’t to create configurable anc headphones but instead to create a device that is able to cancel out the sound of your voice from the ears of other people around you so you can speak in public privately.
The problem is you can’t possibly work out exactly how and when the sound will hit each set of ears around you to be able to direct a beam of sound to their ears (assuming it’s even possible to have such directional sound)
The problem is significantly easier with headphones. You have a headphone and speaker in between your ears and the sound. The distance between the microphone and your ears is constant so you can perfectly time the negative sounds.
I never said it would be easy, but you make a good point. Compensating based on other sets of ears would be tough, because their locations are unknown and change fast.
Directional sound is possible to an extent, Woody Norris gave a TED talk about it a long while back, it is called hypersonic sound. I think it uses ultrasound to generate compressions and rarefactions far away. I realize it sounds like science fiction, but you could perhaps transduce sound to electricity and again to sound, sending the signal of your voice away from you faster than the speed of sound, in time for a cancellation wave to be generated and have an effect. I suppose the analogy would be quiescing a ripple in a pond.
There was a product announced a few years back called Hushme that proposed to accomplish this goal. It attempted to create an acoustic seal around the wearer's mouth, and somewhat predictably, it looked ridiculous: https://www.news.com.au/technology/gadgets/wearables/this-ca...
The utility is limited by the limitations of passive noise attenuation devices. These things are great for the shooting range, because bringing gunfire down to a level that won't damage your hearing is pretty easy. There's no kind of earphones that can just completely block out all sound, though.
