From: Klas Strandberg <>
>
> It's nice to have quality text to read, isn't it....
Especially if it's something that applies to the practical problem at hand.
> One thing which J=F6rg (I have met him and discussed those things) didn't=
> mention is that a windfoam works better, the bigger it is; bigger - not
> thicker.
> The best windprotection is a big tent with no acoustics.
There is a misunderstanding that's common, that the structure is the
protection. The wind protection is almost entirely due to the layers of
still air between the layers of structure of the windscreen. It's the
still air that primarily absorbs the energy of the wind to get it low
enough by the time it reaches the mic. The primary function of the
layers of material is to smooth the wind to a more consistent average
speed. And to allow the formation of the still air. If it actually
stopped the wind, it would also stop the sound.
The biggest problem with a big tent is keeping it from flapping in the
wind and making it's own sounds. Plus it has some real portability
problems and is very hard to hand hold while walking through the brush.
The biggest problem with foam is it's structure. Structurally it's a
whole pile of tubes that connect all the way through it. It can act as a
smoothing layer if it's away from the mic far enough, but the foam
"windscreens" sold with mics are right on the mic. Pipes from wind to
diaphragm.
Foam does also have the problem that wind blowing along it's outer
surface will produce new sound.
In one regard some of the conclusions in the article are a problem.
There is not just one kind of basket zeppelin, they vary in many ways,
including the way the wind passes over their outer surface. Consider
this, the Rycote zeppelins have their fabric fill on the inside of the
large mesh and it's flannel like, the Sennheiser have their fabric fill
on the outside of the large mesh, and it's very fine mesh.
It's also the case that wind protection and suspension is usually our
biggest transport problem. Effective wind protection is large and rigid
enough to stand up to the wind, but to be light it's not all that
strong. The commercial designs are a compromise, being generally big
enough to handle most ordinary conditions, without excessive bulk. It is
in the area of transport and standing up to the wind that homemade
designs often fail the most.
Think about this, I'm about to make a trip that, last time I did it,
covered 8000 miles of driving. That included not just good paved roads,
but everything down to two marks running across the rocky desert.
Sometimes spending hours to days on the latter. All 6 of my stereo mic
setups have to share space with camping gear, photography gear, other
sound gear, field biologist stuff, plus things like clothes, food and so
on. I sleep in the truck too, so they share space with me. The truck is
stuffed. While I protect them well, they will be subjected to all kinds
of environmental insults. And will be expected to be ready to go at a
moment's notice, day or night. Or have mics rearranged as need be within
the setups, and be able to do that quickly.
I'm very good at designing and building things and well equipped to do
so, but I've not come up with anything I could build that will be able
to meet the full specs I use for being a piece of equipment out in the
field and do it significantly better than the commercial suspension and
wind protection gear. Life is too short to spend it just reinventing
that, I can certainly build something just like it but it uses time. So,
I grumble about the high prices and pay them. I do hunt for the best
prices in mostly used gear, often gear needing repair, I don't pay those
new prices people are so fond of quoting. I do modify the commercial
gear where I see it needs improvement as well. Or just to adapt it to my
uses.
Walt
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