The best wind noise reduction is achieved at the time of recording by using every tool in your arsenal; everything afterward will always be a fix, at best. This doesn’t mean that you can’t come up with creative solutions, because at the end of the day, nature does what it wants. So, here are a few ways to help you weed out wind noise.
Firstly, there is plenty of equipment out there designed and sold to help reduce wind noise. The benefits of using prefabbed kits are that these tend to hold up well to fieldwork, and most of the branded stuff out there lives up to what it says on the box.
The limitations can be more price-centric in some cases and whether it will fit a specific bespoke setup remains to be seen, since a lot of products can cater to shotgun microphones. That is not to say that stereo microphone products don’t exist. That said, a tailored DIY solution might be the right approach for less frequent setups where wear and tear are less of a concern–or, if you’re the kind of person that gets a kick out of a good DIY project.
Filters and Fuzzy Things
No matter the shape, design or material, the central concept here is that you are putting something in front of or around of the chassis to prevent wind from blowing across the microphone’s capsule. Each design is gauged on its acoustic transparency, meaning how little the structure’s design and materials interfere with the overall clarity and frequency response. Otherwise, we could just get away with sticking the mic in a box and calling it a day.
Foam windscreens are snug fitting pieces that slide over the microphone chassis. They use open cell foam to help absorb and diffuse sounds and work best indoors. Think back on all the black foam pieces you see attached to shotgun and camera mics.
These are encompassing structures that cover the whole microphone assembly, down to the mounting system. If we’re looking at a shotgun microphone, the assembly will extend all the way to the boom attachment.
Wind can also cause mechanical noise by resonating and moving across the boom and attachments. That’s why sealing up the bottom assembly is key to preventing excess movement.
3. Dead cats
A “dead cat” is a specific kind of fur-covered, scruffy lookin’ blimp designed to take the edge off in what can be referred to as high wind conditions, all while providing a high degree of transparency. A dead cat uses artificial fur to block and reduce wind noise while still allowing for clear pickup.
Think of a furry as a shrunken down dead cat or similar fur covered wind cover. These fit over a lavalier’s capsule and help block and reduce the audibility of wind and clothing noise.
5. Go Away, I’m Hiding!
We’ve covered a heap of lavalier techniques in our article on wireless lavs. One particular method is concealing or hiding the microphone on or around your talent. This can be in their clothing or strapping the microphone directly on their person.
The key is to break the wind’s line of sight and access to the capsule without muffling your audio.
Fake fur and open cell foam are the name of the game here, we’re not talking about building retro 80’s costumes either. This might be the right approach if you find yourself needing something that is price restrictive or unavailable. I can see a custom blimp construction project for a non standard or larger microphone array as a good candidate. While there are products available out there, it might be more practical to build something that tailors specifically to your setup.
7. Finding cover
A simple change of perspective or positioning can be very helpful. Try taking cover behind a tall car or truck, ducking around a wall, or moving behind a tree. Obviously, this is not always going to be realistic. Desert shots don’t have much in the way of cars, walls or trees. In the cases where you do have some cover and a shot can be altered to work with a small rotation or step to the side, you shouldn’t hesitate to test.
Try taking cover behind a tall car or truck, ducking around a wall, or moving behind a tree.
There are many noise reduction tools and plugins that can help reduce or remove distracting wind noise in your recording. Tired of using plugins? While there’s nothing wrong with using them, you can also opt for a more practical and old-school approach that incorporates the basic principles that make up a lot of plugins. There is joy to be found in discovering and applying DIY techniques.
The majority of location recording is dialogue-based, so by that logic you can start cutting unwanted frequencies that fall outside what’s typical for the human voice. Low frequencies carry the most energy and can be highly disruptive. Unless the talent has a hefty baritone, a safe starting point is using the Low Cut Filter on your recorder. These typically roll off frequencies below 150 Hz, so you’re not cutting much out of the average dialogue range.
9. Noise Reduction with Phase Cancelation
This will require a two-microphone setup that records the surrounding environment. An omnidirectional mic will do well here since it will capture the most sound. Position your omni mic far enough from your source so that ambient noise is dominant.
Then, record your source sound with your primary microphone as you normally would, using best practices to optimize your pickup and reduce unwanted noise.
Import your recorded files into your DAW. Next, you’ll need to invert the phase of the secondary channel. The result will cancel out sounds with similar waveforms, that’s why you want to move your secondary microphone farther away from your source. There is a proportion to placing additional microphones to avoid introducing additional phasing and frequency issues to the point where whole articles and books exist on the topic.
A simple way to understand phase is to look at how the audio waves are shaped and how their cycles line up. Take a Sine wave and then imagine two Sine waves, where their peaks and dips are the same amplitude (height). Now take one of the waves and move it horizontally so that the peak of one aligns with the dip of the other. The two identical waves will cancel each other out.
If all else fails…
As with just about everything in life, you can’t assume that a shoot will always go your way. We are talking about weather and nature, after all. Unless you’re living in the eternal sunshine state that is California or somewhere equally consistent in its good weather or rain deprivation, you will probably have to work around the weather. Trust me, I live in England, and just washing the car can require checking the forecast.
So, keep an eye on the weather forecast and have a plan for extra shooting days should you need them.
If you can’t go outside, why not come back in? It’s not fun admitting that you need to re-record, but you always have to put your best foot forward and strive for quality. An ADR session is a good way of getting the wind out of your hair and grabbing a clean recording.
11. Reschedule and try again
We will assume that you’ve done your homework and assumed the best and planned for the worst. You’ve had a few days of bad weather, a few bad recordings, but you have extra days for reshoots. There’s little use in hanging around — get to work and get those shots done! Chances are everyone’s hair was all over the place anyway.