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Re: Noise measurment and figures

Subject: Re: Noise measurment and figures
From: Lang Elliott <>
Date: Sat, 27 Apr 2002 19:15:48 -0400
Klas:

Yes, I would love to see the drawing.

Tonight I'm experimenting with a possible stereo MKH 20 mikes-with-barrier
setup and comparing it to the Stereo DAT Mic, both without mounting in the
parabola. 

My simple test is to put a ticking windup clock in a quiet room, then muffle
the ticking with pillows so that I can just hear it several feet away. Then
I test each mike's ability to discern the ticks at various distances. The
trick is finding the point (= distance from the clock) at which the noise
floor of each mike setup completely obscures the ticking. This is my
poor-man's noise-foor testing technique.

Differences of around 3-4 db or more really show up when I perform this
test.

If the stereo MKH20 setup is clearly superior to the Stereo Dat Mic, then
I'll have to figure out how to mount the double-mikes on one of your dishes.

Lang

> Yes, Lang, you will get a "noise-free" microphone. But remember, using the
> gain which such a very low noise level allows, will bring you into other
> problems - wind noise, ambience, noise from your stomach, clothes, breath.
> Practically, if the noise is lower then - say, 15 db(A) - you can't use it
> anyway unless perfect conditions.
> 
> If you wish to continue, I'll be happy to send you a drawing on how it can
> be made.
> 
> Klas. 
> 
> 
> 
> noireAt 09:44 2002-04-27 -0400, you wrote:
>> Actually, the effect would not be "binaural" because there would be little
>> separation between the two mikes. Nonetheless, the effect is pleasant, just
>> like that produced by the Stereo Dat Mic when used without the parabola.
>> 
>> Lang
>> 
>>> Klas:
>>> 
>>> I have considered trying to mount two MKH 20s side-by-side in a Telinga
>>> dish, with a small barrier between them, such as the one you use for your
>>> stereo DAT mic.
>>> 
>>> With inherent noise of 10ba plus the pzm effect, that should theoretically
>>> result in an incredibly quiet stereo parabolic setup.
>>> 
>>> What do you think?
>>> 
>>> Lang
>>> 
>>> 
>>>> very sorry:
>>>> 
>>>> "2/ An average amplification of PZM is usually estimated to some 6 db.
>>>> Therefore we're down to 10db inherent noise of the stereo DATmic, without
>>>> the dish."
>>>> 
>>>> Should be 12 db(A) of course.
>>>> 
>>>> Klas.
>>>> This outgoing e-mail is scanned for viruses with Norton 2002
>>>> 
>>>> Telinga Microphones, Botarbo,
>>>> S-748 96 Tobo, Sweden.
>>>> Phone & fax int + 295 310 01
>>>> email: 
>>>> 
>>>> org. no SE440130067001
>>>> 
>>>> 
>>>> 
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>>>> 
>>>> 
>>> 
>>> 
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>> 
>> 
>> 
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> This outgoing e-mail is scanned for viruses with Norton 2002
> 
> Telinga Microphones, Botarbo,
> S-748 96 Tobo, Sweden.
> Phone & fax int + 295 310 01
> email: 
> 
> org. no SE440130067001
> 
> 
> 
> To unsubscribe from this group, send an email to:
> 
> 
> 
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> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
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