Hi, Takeshi--
Like you, that has been something we have sought in headphones. "Noise cancellation" only means that the microphone ignores ambient noise. Headphones that give you "audio isolation" - active (with an electronic dampening feature) or passive - such as
those marketed for listening to music, only eliminate white noise - like motors and fans, etc. - from reaching your ears, but they will not eliminate the sound of someone sitting next to you and talking. I did a lot of research on this, and the only headphones
made that might actually block out the voice of someone sitting next to you from reaching your ears MIGHT be some VERY pricey professional aviation headsets, for people working in extremely loud environments.
We have booths in our lab with sound-dampening panels between them. If a kid is leaning back in their chair, talking at the ceiling, EVERYONE hears him. I try to train them early to lean into the booth by putting their elbows on the desktop (I say that
specifically because "lean in" doesn't work) and to pay attention that their audio level meter does not go into the red. I wish I didn't have to spend so much energy shaping the behavior of so many students, and if there was another solution, I'd do it.
Good luck!
Cheers,
Margo
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Margo Burns
Director of The Language Center
St. Paul's School
325 Pleasant St.
Concord, NH 03301
(603) 229-4666
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