From: "Graham M Smith" <>
>
>
>>> I work on the concept of "good enough". It's all fine and dandy to wast=
e
>>> lots of money chasing perfect if it amuses you, but what really counts
>>> is "good enough". If it will get the job done well, why spend extra?
>
>
> Exactly, I have taken some criticism for using Frequency Division detecto=
rs
> and MDs at high compression. But I felt this missed the point, I only nee=
ded
> to separate out Horseshoe bats from the rest, and I needed a lot of sampl=
ing
> stations. The set up I ended up with was perfectly adequate for what I
> needed and had we gone the "high quality" route, the project juts wouldn'=
t
> have happened because of the costs of setting it up.
>
> As it was, we learnt a lot about how the bats were using the study area a=
nd
> because we had the detectors running well into the morning we also
> discovered that the bats were still flying an hour and a half after sunri=
se.
> We also found that, although the radio tracking work had shown only one
> route across the site, or rather just off the site, we had records of
> Greater Horseshoe bats using every linear corridor all over the site. A v=
ery
> different picture to the one given by radio tracking. Of course costs and
> concerns about bat welfare restrict the number of bats that can be tagged
> for radio tracking.
I was amused reading about one study in Florida that suddenly discovered
that Barking Treefrogs were all over the space center wetlands. When
they had not found them before in numerous studies, only one roadkill
specimen. They put out a frog logger to do this. Of course a bunch of
eyes and ears that don't just do their biology 9-5 would have worked as
well. We have some herps people I know of that contract surveys and only
work 9-5, one of my little pet peeves. Frogs are very scarce in their
surveys.
By using stuff and techniques that's "good enough" for the job, we can
advance science much faster than using "best, state of the art".
>>> This is particularly true in science, where funds are always limited.
>>> "good enough" is what you are after.
>
>
> Now if I was undertaking some bat bio-acoustical study then I would
> re-position my views on what is "good enough".
I have stated my views there. For some limited subset of bioacoustics
it's appropriate to use highly calibrated and very expensive equipment.
For that, MD is highly inappropriate. But so is any other standard audio
recorder, not matter if it's compressed or uncompressed. In actuality in
such studies "good enough" has little to do with what is appropriate and
cost effective and all to do with what will be acceptable on peer
review. Those folks have very limited equipment they cling to. And play
scientific potlatch.
Truth is, for what's being studied a lot of those expensive studies
could be done with MD or even less. After all, when I first learned to
do bird sonograms the recorders we were using were no better than cheap
cassette recorders today. Most of the original work on that was done
with such sound quality level. A lot of very good work.
> One web site that did concern me was
> http://www.avisoft-saslab.com/compression/compression.htm
>
> but I assume you are ware of this one.
That's Raimond's attempt at analyzing on paper something he's no
experience with. He heavily overstates his case. And he uses a
contrived test with sounds no animal or group of animals would ever
produce. Testing mp3 compression as if it was ATRAC. Kind of like saying
Fords and Chevys are exactly the same, something that might get you shot
around these parts.
Walt
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