--- In Walter Knapp <>
wrote:
>
> Posted by: "cfmspencer"
>
> > in comparing the likely usefulness of mics for
> > quiet ambient nature recordings, I've been
> > dividing the sensitivity spec figure by the
> > noise spec figure and ranking mics relatively
> > based on the result.
> >
> > by this method, a Sanken mic with 20db noise
> > and 50mV output would rank higher than a Sennheiser
> > with only 12 db noise and 25mV.
> >
> > does this seem a reasonable way to compare, or is
> > lower noise ultimately more important than higher
> > output?
>
> The two specs are not even the same measure. So your method makes
no
> sense. Compare them separately.
thanks for your kind response, Walt,
yes, I know they are not related,
I was simply seeking a sort of calculated
formula that included what I thought to be
the two most important specifications for
nature recording into a single number for
a relative ranking (of sorts). certainly
not scientific
>
> The way I think of it is that the self noise figure tells me
something
> about how quiet a site the mic can record in. Note that even if
> recording loud calls this can be important if the background sound
> levels between the calls are low. Self noise is the floor of the
sounds
> in your recording imposed by the mic. It's more or less
independent of
> the sensitivity, though through the gain of the mic pre the two
interact
> somewhat. Compare it to the noise floor of your site.
thanks, for my purposes, I believe that the lowest noise
mic available that meets other needs, e.g. pattern, and
weatherproofness will be best.
with regards to my 'formula' approach, I was looking to
somehow factor in the sensitivity of a mic, as I assumed
that a mic with high sensitivity will be able to
provide the preamp with a stronger signal-to-noise ratio
even if it's self noise level might be higher than
the lowest available.
>
> Sensitivity probably relates more to the reach of a mic. How much
> distance away it can be from the caller and still make a good
recording.
> Many mics are designed for work on fairly loud sounds right at the
mic.
> We hunt for the few that are designed for more distant pickup, and
then
> push that well beyond their design distance. It does also somewhat
> relate to the self noise, in that greater sensitivity may
seemingly give
> less influence to self noise.
yes, this is exactly what I am hoping to figure out, ideally
with a formula, if this is even possible.
> Sensitivity more is a measure of how much
> you can raise the calls above the mic's self noise floor.
>
>
> > yes, I know, it's not all about specs, and that
> > I will need to work with mics to truly determine
> > what works best for me.
>
> Indeed, too much emphasis is given to the numbers and not enough
to
> field experience.
>
> Indeed, the best specs in the world don't do you much good if it's
the
> wrong mic for the job. Or if it does not tolerate the outdoor
> environment well. Or if it's hypersensitive to handling or wind.
These
> and more are all things you find out by getting out and recording
the
> subjects that interest you.
>
> Mic choice is a personal one. We are all somewhat artists
communicating
> our personal concept of the soundfields we hear. The mics are a
critical
> tool for that.
Walt, I've been reading some of the posts in the archives.
I appreciate that you often tell the reader to get down from the
ivory tower and out into the woods to 'find out for yourself',
that there is NO 'perfect' mic or pattern or setup, and that it is
impossible to know what you need/like without experience.
thanks
clay
>
> Walt
>
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