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Don Pearce[_3_] Don Pearce[_3_] is offline
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Default Frequencies covered by noise cancellation

On Fri, 5 Jun 2009 20:02:27 +1000, "Mr.T" MrT@home wrote:


"Don Pearce" wrote in message
news:4a2fb739.604885062@localhost...
Phones that isolate the HF well also tend to deal with the bottom end
without resort to active cancelling.


Not so, LF is a lot harder to absorb than HF.

You don't absorb it, you block it, which is not the same. Stiffness
and a bit of mass does the job.

Where active phones work well is
in situations like light aircraft where there is a great deal of throb
and drone to get rid of,


That *is* LF noise, and the main reason for NC headphones. The OP wanted
more HF reduction as well, which is beyond the scope of active NC without
placing your head is a vice!


I already went through that in my first post.

Then, because the headshells are lightweight
and not particularly padded, all the other external sounds that you do
want to hear - radios, beacons, your passenger etc, which are not
repetitive - are far better heard than without them. That, as far as I
can see, is the true raison d'etre for active phones.


That may be so for some, IF the manufacturers made that clear to the buyers.
Personally I'd want ones that block LF *and* HF however, which appears to be
what the OP wants as well.


Yup, that has been dealt with to the OP's satisfaction - we've moved
on to another facet now. It isn't an LF/HF thing. It is a
repetitive/non-repetitive differentiation. You need to hear the
one-off events while blocking the background drone. That is where NC
phones score over block-everything passives.

d