Callan Cohen wrote:
>
> Hi,
>
> I've been recording bird (and frog) sounds for a few years on a relatively
> amateur level, although I've found many of the recordings most useful for
> birding, frog atlassing and scientific purposes. I use a Sennheiser ME67
> (the long shotgun mic with a K6 power pack) and have recently moved to a
> Sony minidisc M700(?) from my trusty Sony cassette recorder TCM5000EV.
>
> I have a question for the NatureRecordists regarding prevention of wind
> distortion. I initially used the foam cover that was suppled with the mic
> but then invested in a "fluffy dog" Rycote Softy because I found that some
> environments were too windy. I've been less than impressed with the
> Rycoyte's performance (although it is definitely a step up from the supplied
> foam) and find it often unacceptable bulky.
The foam is really only intended to break up the breath sounds from the
person speaking and provide some protection of the mic. Really just
indoor or calm outdoor. It provides protection for the mic keeping dust
and dirt out of the mic and some cushioning of bumps.
The softie is a bit better as the fluffy outer layer slows the wind some
and smooths it before it goes through the cover.
Both of these have the disadvantage that they are direct on the mic.
This means the pores the sound comes in become little air rams for the
wind banging right on the diaphragm. And the cover itself can transmit
any movement the wind imparts mechanically. Thickness is not much of a
advantage in foam, you quickly reach a thickness where additional does
not help. To get better you have to use a layering approach. In this you
have airspaces to dissapate the wind that gets through each layer. And
if you thought the softie was bulky you have seen nothing yet. The next
step up is the zepplin windscreens, often covered on the outside with
fur like the softie, they also have their own wind dissapating layer.
And then inside of them there is airspace to the mic. You may still be
using the foam or softie inside that if conditions are really bad. The
whole kit works out at least 3 - 4" in diameter, probably at least 6"
longer than the mic plus connector combo. But when you get done you have
something than can reliably be hand held is pretty stiff wind and get
the recording. For sensitive shotgun mics it's pretty essential.
That level gets real expensive to buy. Rycote sells it as three parts,
the suspension that shockmounts the mic inside and mates to the
windscreen, the zepplin windscreen and the outer cover of fur or fleece.
For my MKH 816 shotguns that combo costs more than I paid for the mics.
So, I'm in the middle of building my own equivalent. I currently have
mine with foam covered by a light fur sock arrangement I built as a
temporary measure so I could use them. That seems to work for light,
non-gusty breezes, but still hard to keep down handling noise. And
tricky to hold as I want to use the two as a stereo pair.
> I'm leaving soon on a birding trip to Cameroon, Central Africa, where the
> majority of my recording will be of birds in the relatively wind-free forest
> interior. Because both the Rycote softy and the supplied foam cover are very
> bulky, I'm considering making a compact wrapping for the mic from a high
> density foam, perhaps 0.5 mm thick? Does anyone have any advice concerning
> this? What density does the foam need to be? How thick should it be? The
> thicker, the less wind but also the less signal, I assume? Any advice will
> be gratefully received!
It will work less well than the foam or softie. About all it will do is
provide the dust/dirt protection. And, unless chosen very carefully,
will change the sound, probably dropping the high frequencies a lot. The
choice of material for windscreens is tricky and there don't seem to be
any collection of tables as to what works and what does not. Only trying
to copy other setups that do.
I strongly suggest you read this article:
http://www.equipmentemporium.com/windscre1.htm
He's talking about movie and TV sound recording, but virtually all he
says applies.
Walt
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