Taperssection.com
Gear / Technical Help => Ask The Tapers => Topic started by: deadheadcorey on September 04, 2012, 09:59:53 PM
-
so whats the best way to edit out wind phasing?
-
Easy - you can't.
Try listening to one channel at a time - possible phase shift might not be as pronounced as mono.
-
20/20 hindsight, windscreens, and a time-machine...
Sorry bro... I hope it wasn't too important of a Tape!
Terry
-
it isnt so bad. somewhat of a windy night up at the Mishawaka Ampitheatre, kinda sucked but what can you do. i sure it would've helped if i had some dead rats
-
http://www.thewindcutter.com/shop/ A pair of Windcutters over DPA screens work great!
it isnt so bad. somewhat of a windy night up at the Mishawaka Ampitheatre, kinda sucked but what can you do. i sure it would've helped if i had some dead rats
-
Windscreeens help, but the more directional the microphone pattern, the more suseptible to picking up wind noise.
Consider omnis if it's more than breezy, foam screens alone are often enough with them IMO.
-
So if you are talking wind phasing rather than wind rumble there is nothing that I have heard of that can be done in post and wind screens or dead rats would not have helped. Wind phasing sounds like the music swirling from side to side and the only thing that can be done is to get closer to the source at the show. Generally you can hear music swirling while you are standing at the show and the mics are going to pick this up. The more directional your mics are the more the phasing will be an issue. It generally does not come through as much with omnis.
Now, wind rumble or noise is a different story. This can be avoided at the show with wind screens and dead rats. It can also be reduced, sometimes significantly, in post by using a high pass filter. Most of the rumble is usually in the extremely low frequencies. You will then have to strike a balance between removing the rumble and removing the bass from your recording. I have done this a few times recently with what I considered decent but not great results. The recordings ended up with a lot less bass than I wanted but the wind rumble was so annoying to me it was worth it.
-
So if you are talking wind phasing rather than wind rumble there is nothing that I have heard of that can be done in post and wind screens or dead rats would not have helped. Wind phasing sounds like the music swirling from side to side and the only thing that can be done is to get closer to the source at the show. Generally you can hear music swirling while you are standing at the show and the mics are going to pick this up. The more directional your mics are the more the phasing will be an issue. It generally does not come through as much with omnis.
Now, wind rumble or noise is a different story. This can be avoided at the show with wind screens and dead rats. It can also be reduced, sometimes significantly, in post by using a high pass filter. Most of the rumble is usually in the extremely low frequencies. You will then have to strike a balance between removing the rumble and removing the bass from your recording. I have done this a few times recently with what I considered decent but not great results. The recordings ended up with a lot less bass than I wanted but the wind rumble was so annoying to me it was worth it.
^^This
For wind rumble low cut filters on mics, recorders or mic pres can be employed too but it is easy to roll off the lows with more control when editing.
Edit to: strikeout the bit about omni's reducing wind phasing as Gutbucket points out in reply #10. You can certainly hear the phasing with your own ears at the time and any mic pattern will hear it too.
-
Out at Telluride we would put a piece of speaker fabric over the capsule of the mic before putting on the windscreen, which did a lot to address the low-end rumble. I quit taping there because the shit is just outta phase even if you don't get rumble.
-
So if you are talking wind phasing rather than wind rumble there is nothing that I have heard of that can be done in post and wind screens or dead rats would not have helped. Wind phasing sounds like the music swirling from side to side and the only thing that can be done is to get closer to the source at the show. Generally you can hear music swirling while you are standing at the show and the mics are going to pick this up.
Yep, gusty wind modulates the sound waves by pushing the air around which they are traveling through, producing the swirly sound. You bring up a good point in drawing a distinction between wind phasing and wind rumble.
The more directional your mics are the more the phasing will be an issue. It generally does not come through as much with omnis.
I have to differ here, choice of pattern won't make much difference with wind phasing. The phasy sound happens in the air before the sound even reaches the mics. The only significant way of combating it is to move closer so there is less air blowing around between the mics and the source and therefore less phasing. As you mentioned, if you can hear it you'll record it, regardless of pattern.
Now, wind rumble or noise is a different story. This can be avoided at the show with wind screens and dead rats. It can also be reduced, sometimes significantly, in post by using a high pass filter. Most of the rumble is usually in the extremely low frequencies. You will then have to strike a balance between removing the rumble and removing the bass from your recording. I have done this a few times recently with what I considered decent but not great results. The recordings ended up with a lot less bass than I wanted but the wind rumble was so annoying to me it was worth it.
This is spot on. But I'll add that wind rumble is where using a less directional mic does help- and is the most basic way of reducing susceptibility. From that basic susceptibility, other measures such as foam screens, furry covers, hollow screened 'blimps' further improve wind rumble resistance from that by creating 'dead air' space around the mic, isolating the capsule from the chaotic wind pressure immediately around it. If that is still not sufficient, low-cut can help but sacrifices the bass.
To contrast wind phasing and wind rumble, the difference is that wind phasing is caused by chaotic air motions blowing sound pressure variations around ‘out there' between the source and the mic. Wind rumble is also a disruption in sound wave pressure variations, but is chaotic pressure variations acting locally on the mic capsule, where we can do things to minimize it. Windscreens, rats and blimps would work against wind phasing too.. if they were scaled up to the size of a room and calmed the motion of all the air between the mic and the sound source!
I was looking for a link to an excellent article AES article on wind noise by Jörg Wuttke explaining much of this in detail and going further in some interesting details about how wind screens affect not just frequency response, but also compromise directional polar patterns but it isn’t available online anymore. Here’s a WaybackMachine (http://web.archive.org/web/20050819052458/http://www.filmebase.pt/Wind.html) archive of it. I also found this article (http://www.microphone-data.com/media/filestore/articles/Wind%20and%20vibration-10.pdf) by another author while searching for it, which looks similar if less in depth technically, but I haven’t read that one.
OK, enough of this noise..
-
Conclusion of the article on wind noise prevention by Jörg Wuttke of Schoeps-
7 CONCLUSIONS
Foam windscreens should be used wherever the protection they offer is sufficient, for their negative effect on the sound is relatively small and easily correctable. On pressure transducers they are almost always the best choice.
Basket-style windscreens must be used on directional microphones if foam types are inadequate to reduce the levels of wind interference. They do detract from the sound and directivity of a pressure-gradient transducer to the degree that they are small and efficient.
A good compromise between the two types is a hollow foam windscreen. In all cases care must be taken to avoid overloading the microphone channel ' s input electronics due to the excessive very low and even infrasonic frequencies produced by the action of wind on the microphone diaphragm. Attenuating the system's low-end response at the earliest opportunity is always a good idea to ensure a clean transmission.
-
A good compromise between the two types is a hollow foam windscreen. In all cases care must be taken to avoid overloading the microphone channel ' s input electronics due to the excessive very low and even infrasonic frequencies produced by the action of wind on the microphone diaphragm. Attenuating the system's low-end response at the earliest opportunity is always a good idea to ensure a clean transmission.
That would lend support to using roll-off filters on mics, preamp or recorder if you've got them as opposed to doing it in post.
-
sorry guess i was confused on wind rumble vs wind phasing. i had to deal with wind rumble. here is the final product after editing some wind rumble out and mastering it http://www-tracey.archive.org/details/7walkers2012-09-01.fob.mc803.kindrec
-
deadheadcorey, the problem of course is that wind rumble extends from very low frequencies (below 20 Hz) up into the audio midrange, and is highly dynamic. Those two characteristics mean that some wind effects can't be filtered out effectively after the fact, even with the most advanced dynamic filtering systems such as Cedar. For wind problems, "an ounce of prevention is worth a pound of cure."
--best regards