Hi Klas,
The idea of response changes with low temperature seems entirely reasonable=
. Can you
suggest from tests or speculate on what would happen to sensitivity and fre=
quency
response?
We've been running bat detectors with broadband condenser microphones outsi=
de every
night through the winter at temperatures down to -25 C and recording bats a=
t air
temperatures well below freezing. It would be very useful to know whether s=
ensitivity at
10 or 20 KHz is substantially lower at, for example, -5 C and whether this =
depends largely
on membrane effects or whether effects on the circuit are sufficiently impo=
rtant that one
needs to test specific microphones.
Thanks,
Bill R.
> Hi Curt!
>
> First of all, the membrane gets colder and stiffer. The electronics
> is specified at +20 and will behave differently. (Though both will
> happen with electrets as well)
> Moist is very critical to the polarizing voltage and the impedance
> from the capsule itself is at gigaohm level.
> The only mic I know which is manufactured for such conditions is the
> MKH series.
>
> Of the other mic's, the NT1A is the best I have tested, so far.
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