Protecting microphones from the wind

Wind is soundless, but the sound of wind as it moves across various surfaces can be one of the more interesting things to record in a soundscape.  However, wind rushing across a microphone can destroy a field recording.  A light wind can be filtered out using a high-pass filter, but if you wanted to include the deep rumble of thunder, for example, even light filtering can take the heart out of a recording.

Most “pro-sumer” recorders and many mics come with a piece of foam to shield the mics from the wind.  These are really only good indoors.  In general, you need to keep the wind off of the mic capsules, and this can be done in several ways.  Some options can be quite expensive, and the Nature Recordists group often referenced DIY alternatives, so that’s where I started.  However, if you don’t want to make your own, fur covers from Rycote, Rode, and Sennheiser are quite good.  There are a number of cheap knock-offs from China available now, but they are reportedly inferior.

The basic concepts

You need to keep wind off of the mic capsules.  This can be done using foam covered with fur, or using a cage to hold a fur cover off of the mic.  The big furry sausages at the end of boom poles that you see the sound guys using in video production are examples of these cages (known as zeppelins or blimps).  Most of these also incorporate shock protection, as most mics are sensitive to handling noise.  Other materials can also be used to cut the wind, for example, lycra or even mosquito netting.  Both of these need to be held away from the mic capsules.  Because wind may create noise as it passes over the surface of these materials, it helps if they are covered with something that literally breaks up the wind, such as fur or another soft fluffy material.  The longer the fur, the greater the wind protection.  Depending on materials used, the particular microphone, and the recording conditions, it may take more than one form of wind protection.  If a fur cover isn’t completely cutting it, putting the microphone in a small “tent” of netting (tulle or mosquito netting) can help a lot.

The simplest forms of serious wind protection include a fur cover over foam that surrounds the mic.  Some examples of these include Auray WSS-2014, K-tek fuzzy slip-on, Rode WS6 deluxe, Rycote softie, and Sennheiser MZH 600:


Professional systems include a shock mount, a zeppelin, and a fur cover. Rycote, in particular, makes modular systems so you can get each component, even different parts of the zeppelin, individually.  Some entire systems include K-tek zeppelin, Neumann WKE 81, Rycote Windshield kit 2, Sennheiser blimp system, and the Shure A89LW.  Most of these come in different sizes for different sized microphones.


Note that those systems are for shotgun mics. If you are using stereo mics, things get more complicated. But a few manufacturers do make blimps that encompass the whole array, including Rycote stereo extended ball gag, Rycote stereo windshield kit AE, Rycote stereo windshield kit AD, Rycote stereo WS 4, and Schoeps WSR ORTF.  Another alternative is to use something like a Rycote baby ball gag on individual mics in a spaced array like ORTF.  For most of these systems, you are going to want the fur covers over the blimps.

One key element in wind protection is “acoustic transparency.”  Materials that cut the wind also tend to affect the frequency profile of the recording.  Fur tends to reduce high frequencies.  Sometimes this is advantageous, as it tend to make the recording sound less “hissy.”  But if you want to record something in the upper ranges, you need to be careful with fur.  If you get the chance to try out blimps made by different manufacturers, pay attention to not only how much the wind is calmed, but how much the outer covering might be muffling the sound.

You also need to be careful with some windproof fabrics, including windproof fleece.  These materials can muffle the sound.  Likewise, recording from inside a camping tent covered with a rainfly tends to muffle the sound.

What I currently use

I have done a lot of experimenting with different materials and fabrics.   I finally purchased a couple of Rycote Baby Ball Gags and Windjammers.  These are way better than anything I came up with, and I think they are worth the price.  Rycote adds extra layers to both the gag (blimp) and fur cover.   I also use either Rycote or Bubblebee lav covers for some of my Clippy mics, sometimes with a small DIY blimp made of hardware cloth, fabric liner, and faux fur.  For my SASS array, I use multiple layers of lycra, with a layer of fur on top if it’s really windy.   I use Movo or Rycote covers for handheld recorders with built-in mics.  

I record in very windy environments, and I have yet to find anything that can handle high and gusty winds.  I often use the landscape as much as I can to block the wind, especially placing the mics near the ground next to a bush, tree, or rock.  

 

Additional sources of noise

In addition to wind hitting the mic capsules, you also have to worry about the effects of wind on cables and tripods. I use Velcro cable ties to snug the cables to the tripod.  Tripods can “sing” if the wind hits them just right; supposedly carbon fiber tripods are much quieter.


Last modified May 2022.

2 thoughts on “Protecting microphones from the wind”

  1. Regarding Tripod singing you mentioned at the end. This is probably caused by vortex shedding in the airflow past the straight parts of the tripod. See https://en.m.wikipedia.org/wiki/Vortex_shedding . The solution is also given in the section ‘Mitigation of vortex shedding effects‘ where they describe ‘Scruton strakes’. Simply put, wrap a piece of wire or cord in a spiral around the straight sections that are causing the sound. This breaks up the flow and stops the hum. See the picture of the chimney with the spiral strakes/fins to get the idea.

    1. Jeremiah, thanks for the input and the interesting link. I’ve never noticed the hum on any of my recordings, but there are usually enough other sounds that might mask it. It’s good to know there is an easy solution.

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