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David Nebenzahl David Nebenzahl is offline
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Default Frequencies covered by noise cancellation

On 6/7/2009 6:59 PM Mr.T spake thus:

"David Nebenzahl" wrote in message
.com...

Let me guess: it (inverting the signal) would work fine at low
frequencies, but progressively worse at higher frequencies?


*IF* you could provide a 100% accurate signal of the actual sound in the ear
canal,


Well, that's the hard part here, isn't it? But seemingly not impossible
(well, not 100%, but close enough).

and reinject a perfectly matched inverted copy in exactly the same
spot,


Trivially easy, no? A simple phase inverter oughta do the trick.

with no phase shift whatsoever, then the rest should be very simple
indeed :-) :-)


Since we're talking audio frequencies ( 8 kHz, I'm guessing), shouldn't
be a big deal.


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Found--the gene that causes belief in genetic determinism