None of the others in town have these, thought it was unusual enough to share

  • SpaceNoodle@lemmy.world
    link
    fedilink
    arrow-up
    3
    arrow-down
    1
    ·
    11 months ago

    No, the point of MP3 is to compress audio in a lossy manner while minimizing the introduction of artifacts detectable by human hearing using psychoacoustic analysis. The coincidence that the necessary parasitic EM signal induced by speaker drivers happens to be created by a signal that doesn’t suffer degradation by a relatively specific lossy compression method is remarkable.

    • Chobbes@lemmy.world
      link
      fedilink
      arrow-up
      3
      arrow-down
      1
      ·
      11 months ago

      Right, but artifacts in the ~8khz range will be detectable by human hearing. mp3s are going to be perfectly acceptable for many sounds in that frequency range… The fact that this works is evidence of that.

      Plus, you know what else is lossy? Radio. If the signal is that fragile there’s a good chance the locking mechanism wouldn’t work in the first place.

        • Chobbes@lemmy.world
          link
          fedilink
          arrow-up
          2
          arrow-down
          1
          ·
          11 months ago

          It’s just going to be pulses of an 8khz signal. Why would an MP3 not encode this just fine?

            • Chobbes@lemmy.world
              link
              fedilink
              arrow-up
              2
              arrow-down
              1
              ·
              11 months ago

              It’s a bit of a coincidence that the signal is in the audible range, for sure! I’m not too surprised that an MP3 can reproduce a digitally modulated sin wave in the audible spectrum, but I can see how it’s surprising to people that a sound card is basically a dinky low frequency SDR. Van Eck Phreaking is another good example of this kind of stuff. CRTs in particular produce very obvious emissions which match what’s being displayed.