Thanks Raimund.
The linearity argument makes sense, at least over a broad range of
pressures. However, with varying designs, I'm still not sold on the idea
that they would all have the same slope.
I quite willing to be convinced, though :)
k
On Fri, Mar 15, 2013 at 1:56 AM, Raimund <>wrot=
e:
> **
>
>
> > Yes,
> > typically we only get one number for that at a 94 dBSPL test figure, bu=
t
> it
> > doesn't follow that the mV/Pa is a linear function over varying
> pressures,
>
> Keith, common microphones have a linear characteristic. So, the mV/Pa
> specification is valid for any sound level (except of clipping and very l=
ow
> levels that are masked by the self-noise of course). If that was not true=
,
> the microphone would introduce severe distortion.
>
>
> > Let's say we have our scene with a distant source of particular interes=
t
> > producing say, 10dBSPL less than some other nearer source.
> >
> > Now, let's assume for this purpose, we have 2 gun mics with the same
> polar
> > pattern and the transfer functions are both linear but have different
> > slopes. #1 has a sensitivity of 20mV/Pa, #2 is 10mV/Pa, - I'm guessing =
#1
> > likely has a steeper TF slope than #2. Both have a sufficiently low
> > self-noise to be used for nature work and our mic pre's are near
> > noiseless, at the gains applied. We adjust gains so that both mics are
> > reading the same max dB value.
> > I'm thinking the less sensitive mic will do a better job of 'fetching'
> the
> > more distant sound since the difference between the source-of-interest'=
s
> > output voltage and that of the near sound will be less.
>
> Both microhones should provide exactly the same results under these
> conditions.
>
> Regards,
> Raimund
>
>
>
--
Keith Smith
Keith Smith Trio, Northern Lights =96 Altai Khangai - www.keithsmith.ca
Photography - www.mymountains.ca
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