Hi Bill!
I can only say that I have observed other performance at low
temperatures, as a lower output / more mic noise. Several mics have
made pop-corn noise.
It would be, and seems to be, quite random: I bought a pair of
CAD179, one of them is working fine, while the other is not. I bought
a pair of NT1A's and one of them is "popping" now and then, but not
that it disturbs me.
Rob, I am almost certain that it is the same double membrane capsule
in R=F6de 2000 as in NT1A, just other electronics.
Electrets suffer likewise of a hardening membrane, but haven't the
problem with polarizing voltage. Output will get lower, but they will
not "pop".
Klas.
At 06:46 2008-06-05, you wrote:
>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 frequency
>response?
>
>We've been running bat detectors with broadband condenser
>microphones outside every
>night through the winter at temperatures down to -25 C and recording
>bats at air
>temperatures well below freezing. It would be very useful to know
>whether sensitivity 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 important 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.
>
>
>
>
>------------------------------------
>
>"While a picture is worth a thousand words, a
>sound is worth a thousand pictures." R. Murray Schafer via Bernie Krause
>Yahoo! Groups Links
>
>
>
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email:
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