I was the one misinforming! I am sorry, I mixed it up with another micropho=
ne.
Klas
At 20:47 2014-02-20, you wrote:
> > Nt1a have only one membrane so it does not have fig-8 option as David
> > mentioned.
>
>Someone said it has two diaphragms, but one is enough to get a cardioid
>pattern. The misconception was that the two diaphragms work separately.
>There is only one output connection at up to 1000MegOhms impedance, hence
>the need for good screening.
>
>An Omni capacitor (condenser) mic has a solid backplate and this picks up
>rear sounds which diffuse around the capsule but remain in phase with the
>front. This causes some attenuation in higher frequencies which can be see=
n
>in the polar diagram, but it essentially omnidirectional.
>
>A fig-8 version has a perforated backplane, and rear sounds produce the
>opposite phase to the front sounds as it is now working as a velocity
>microphone, not a pressure mic. Sounds from the sides cancel out hence the
>figure of eight polar pattern.
>
>Combining both principles, a cardioid has a partially perforated backplane
>with small holes which cancel out the rear sound as it combines the effect
>of the two types above. This still only needs one diaphragm and one
>backplane.
>
>The tricky part is getting a nice flat response and an acceptable cardioid
>polar response at all frequencies which is what you pay your money for.
>Having a second, rear, diaphragm is used by some manufacturers to get a
>better polar response. The two diaphragms are connected, normally both to
>ground.
>
>David Brinicombe
>
>
>
>
>------------------------------------
>
>"While a picture is worth a thousand words, a
>sound is worth a thousand pictures." R. Murray Schafer via Bernie Krause.
>
>Yahoo Groups Links
>
>
>
Telinga Microphones, Botarbo,
S-748 96 Tobo, Sweden.
Phone & fax int + 295 310 01
email:
website: www.telinga.com
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