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View Full Version : Bose noise-cancelling ears?


DanP
April 30, 2002, 08:48 PM
Had the pleasure of wearing a pair of these in the past over trans-atlantic flights, amazing how they give silence a new definition.

Have the opportunity of aquiring a pair for very little monetary exchange, are these any worth at range / gunshot DB levels?

I may pick them up anyway for a close buddy who is a private pilot, but kind of want them for me.

Thanks in advance for any comments!

JohnKSa
April 30, 2002, 09:18 PM
Noise cancellation is useful for steady noise like airplane engine noise, it is not very effective against impulse noise (sudden sharp noises) like gunshots.

I don't know anything about the Bose system. It's possible that it has a noise limiter incorporated which would be useful against impulse noise.

To be sure, you should contact Bose and ask them.

bountyh
May 1, 2002, 12:21 PM
DanP: noise cancellation is accomplished by producing a sound with the same frequency content but out of phase with the original so that the sound waves arriving at your ear are reduced through cancellation. It is effective for steady droning noise especially the roar of an engine (it's also being used in some high-end autos through the stereo system). It doesn't work for short duration pulse sounds.

DanP
May 1, 2002, 08:14 PM
Thanks folks, that is pretty much what I thought...

I suppose I was hoping that it the system would be fast enough to react & counter.

Anyone know what principle regular electronic ears (as in the ones sold specifically for hunting / shooting) operate?

Snowdog
May 2, 2002, 07:24 AM
Interesting concept.

I wonder in reality if the noise truly is cancelled out or if it is just masked from detection.
I wonder if one is still exposed to the decibel rating from the noise in which they are trying to avoid.

DanP
May 2, 2002, 09:31 AM
Hmm. I wish I knew enough to understand this better.

My guess would be that active noise "cancellation" (by mirroring the signal) would in fact drop the dB level, and that is its product and benefit.

Therefore effective in terms of preventing hearing damage.

It would also seem that lower spectrum sounds would be easier to counter due to wave characteristics.

I do think that the limitation is reaction speed, for example a manufacturer stated that it'd be fine against "slow music" (emphasis on slow).

Oh well, so not for shooting application.

But I wonder if one could tune it to the incessant drone of some female voices...;)