>
> > My friend J=F6rgen makes the best mics in the world (self noise down at=
6
> > dbA!! and perfectly linear) - but we have many times concluded that it
> > would be better to make electrets, if we could only get hold of electre=
t
> > material, either for the membrane or a semi-conductive plastic material
> > which could be charged and used for electrodes.
>
>Wow, that's really low! Is this noise level typical for my Telinga mics?
no, I wish it were, - your Twin Science mics are usually between 12 - 14
dbA, the lowest noise for the omni.
>I am still puzzled as to why the membrane sticks to the electrode is there
>moisture on the surfaces that causes them to stick due to surface tension?
Microphone makers in common make their mic's for indoor use. They don't
care all the way to check what happens in humidity.
Humidity will change the whole design! Just consider the distance between
the membrane and the electrode, it might be only some 5 thousands of a
millimeter! (Imagine temp. variations!)
When the membrane hits the electrode, caused by wind for example, - the
polarizing voltage acts like static electricity, holding the membrane stuck=
until you switch the voltage off.
If you make the membrane stiffer, to prevent this, the mic will get less
sensitive and more noisy.
The perfect mic is the perfect compromise between lots of such parameters.
Klas.
>
>"Microphones are not ears,
>Loudspeakers are not birds,
>A listening room is not nature."
>Klas Strandberg
>Yahoo! Groups Links
>
>
>
>
Telinga Microphones, Botarbo,
S-748 96 Tobo, Sweden.
Phone & fax int + 295 310 01
email:
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