this post was submitted on 21 Sep 2023
211 points (95.7% liked)

Technology

59390 readers
2560 users here now

This is a most excellent place for technology news and articles.


Our Rules


  1. Follow the lemmy.world rules.
  2. Only tech related content.
  3. Be excellent to each another!
  4. Mod approved content bots can post up to 10 articles per day.
  5. Threads asking for personal tech support may be deleted.
  6. Politics threads may be removed.
  7. No memes allowed as posts, OK to post as comments.
  8. Only approved bots from the list below, to ask if your bot can be added please contact us.
  9. Check for duplicates before posting, duplicates may be removed

Approved Bots


founded 1 year ago
MODERATORS
 

Noise-canceling robots to 'mute' loud conversations in cafe | What if we told you that we can actually silence a noisy table right next to us in a café?::undefined

you are viewing a single comment's thread
view the rest of the comments
[–] [email protected] 74 points 1 year ago* (last edited 1 year ago) (16 children)

I've always thought phase cancellation technology could potentially be crazy revolutionary. Seems these guys know what they're doing, but the real challenges come with high decibel levels if I remember right.

If you tried to phase cancel out the sound of a jet engine, it would work and you wouldn't hear it, but you could also have easily just burst your eardrums too, because the sound pressure level is still present, even if the actual sound is inaudible. It's a crazy phenomena.

Edit: the sound pressure level IS cancelled out by destructive wave interference, but if this is knocked even by a matter of milliseconds, the wave is doubled and that's not good for anyone.

Also, on retrospect, phenomena was poor word choice. It's physics.

[–] [email protected] 22 points 1 year ago (9 children)

Wait, what? Doesn’t phase cancellation actually cancel the waves? How can it be inaudible but still present?

[–] [email protected] 24 points 1 year ago (5 children)

The waves are canceled (i.e. gone) until something goes wrong. You could end up accidentally causing constructive interference, in which case you my double the sound's amplitude.

[–] [email protected] 2 points 1 year ago (2 children)

I feel like this doesn't happen very often though. I mean I wear sound canceling headphones all the time and I've never noticed it accidentally making anything louder. Then again, I don't normally stand near jet engines.

[–] [email protected] 4 points 1 year ago

I wouldn't imagine noise cancelling headphones would have the ability to output high enough for serious damage. But some people do experience discomfort and pressure when using noise cancelling headphones for the first time, this could be due to a number of factors though.

[–] [email protected] 2 points 1 year ago

My noise cancelling headphones make wind noise much louder when it's really windy.

load more comments (2 replies)
load more comments (5 replies)
load more comments (11 replies)