EPFL researchers have developed a 100% effective, ultra-thin active noise cancelling system that uses an ionized air plasma propulsion system instead of speakers. A 17mm (0.6 inch) thick layer can block 20 Hz noise as well as a 4m (13 ft) thick wall.
  • Bubble Water@beehaw.orgEnglish
    1·
    1 year ago

    I wish I had one of these to cancel the fireworks in my neighborhood that have been going off all week into the night

    • jabib (he/him)@beehaw.orgEnglish
      1·
      1 year ago

      I saw a lady wearing a shirt that read “I can’t hear you over the sound of my freedom ringing 🦅🦅” so maybe if you just lean into the 'Murica it’ll be quieter?

  • totallynotsocsa@beehaw.orgEnglish
    1·
    1 year ago

    The problem with all of these devices is that there is a lot of noise power in the world. A jet engine is loud because the acoustic energy it produces displaces large volumes of air very quickly. To cancel that energy, you also have to move huge volumes of air. Headphones are good at this, in part, because they attenuate so much energy in the first place with an over ear headphone, or well sealing IEM, and place the speaker very close to your ear. A source of acoustic energy which is D meters from your ear has to produce at least D^3 more joules than a speaker right next to your ear, to cancel the same amount of noise. It’s possible, kind of, with very big speakers, but a handheld device just won’t cut it.