I'm sorry for my late reply. I have been absent from my computer for a
while..
My example shows the principle of the Marantz PMD 6xxx series
recorders. Those recorders do not allow to adjust the preamp gain
(except of the -20dB MIC ATTEN pad). Yes, it is true that one could
benefit from an adjustable premplifier while recording very loud
sounds. However, there are seldom very loud sound events in the field
that would clip the preamplifier.
Please also note that the information on http://www.avisoft.com is
primarily adressed to scientific researchers who investigate animal
sound communication. This application seldom requires extremely low
noise sound recording.
Regards,
Raimund
"userno232000" <> wrote:
>
> --- In Curt Olson <cro@> wrote:
> >
> > Raimund,
> >
> > Thank you for all your work on noise measurements! I have a
> followup
> > question for you and entire wider brain trust here...
> >
> > On your page
> >
> > http://www.avisoft.com/recordertests.htm
> >
> > You state: " Note that a bit-depth of 24 bit would not improve the
> > noise level figures at these high gain settings."
> >
> > And on your page
> >
> > http://www.avisoft.com/tutorial_mic_recorder.htm
> >
> > You similarly state: "Besides the fact that there is no reason to
> worry
> > about the Marantz PMD671 preamplifier noise, it turns out that the
> > optionally available 24 bit recording format cannot provide any
> > significant improvement of the noise performance."
> >
> > If, as you seem to indicate, there isn't much to loose with 16 bit,
> and
> > definitely something to gain (less consumption of blank media and
> > battery power, plus faster transfer times afterward), what
> compelling
> > reasons do we have to prefer 24 bit for capturing our original
> field
> > recordings?
> >
> > Still conflicted after all these years,
> >
> > Curt Olson
> >
>
> Another question while you're at it. You show a fixed 48dB mic
> preamp, certainly there is a preamp gain adjust, isn't there? As
> shown a "hot" mic would overload the preamp at some very low level(a
> few mV). At field recording levels you might always turn it up
> to "11", but other users might not. With the right external preamp
> going into the line input you should be able to take advantage of the
> 92dB number, this is not clear.
>
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