35db of isolation. You basically can't hear anything, which is nice when you need to work somewhere noisy, or want to listen to music on an airplane. It's infinitely better than noise cancellation.
Thank you. I recently spent $80 on another brand that uses foam tips. It had the highest rating I could find amongst the choices at a specialty shop, at IIRC 31 dB attenuation. I haven't been in a suitable work environment since then, to try them out.
I'll probably give those a go, first, but if they do not suffice, these look worth trying, and at about $120 are within my price range (as opposed th the $300 plus that I've seen for some other items).
As you say, though, these work via passive blocking and not active cancellation. Some time ago, I came across an explanation by an audio engineer claiming that cancellation will never work fully with headphones. Even if the processing is fast enough, he argued, the distances involved between the speaker and eardrum just won't permit it. Perhaps this was in combination with the inertia and therefore delay in the speaker elements; I no longer recall fully.
When people state "wear canceling headphones", I've never yet seen the statement backed up with a real / real world use case.
EDIT: I guess/imagine it might be more a matter of the location of the microphone that drives the noise cancellation, than that of the speakers. Although I do seem to recall also something about the limitations imposed by pressure waves operating in such a small, confined space.
http://www.amazon.com/Etymotic-Research-Portable-Earphones-B...
35db of isolation. You basically can't hear anything, which is nice when you need to work somewhere noisy, or want to listen to music on an airplane. It's infinitely better than noise cancellation.