Wind and the microphone
For those of us lucky enough to live in the West, one of the major problems plaguing the outdoor videographer is the ever-present wind.
Perth just happens to be among the three windiest cities in the world.
The old foam sock over the mike is not the answer, and the situation has driven me to investigate other solutions.
I found at an early stage that just shoving something over the end of the mic doesn't always fix things up. For one thing the type of material used can be an important factor.
The unit described here is the result of a lot of fiddling about and I would like to take lots of credit for the original idea. Unfortunately this is not the case as the inspiration came from a commercial unit that I saw during my spell in broadcasting at the Sydney Olympics. The fact that they cost several $k's drove me to the design outlined below. For those of you who just can't get enough science, there's a good article which was presented to the Audio Engineering Society New York in 1991 at www.filmebase.pt/Wind.html
Click for a larger version
The unit pictured was built from 90mm PVC stormwater pipe, a pretty dirt-cheap mop with a telescopic handle, a couple of tea strainers, a bicycle tube, and some imitation fur. It looks pretty much like the real thing and, better than that, works perfectly out in the Perth wind. I must point out that I don't own a fully equipped workshop or hold a degree in engineering. This is something that a person with average skills can make with average household tools.
The PVC pipe needs to have 1.5mm wall thickness to make the assembly stable. A prototype unit was made with thinner pipe and tended to wobble about. The different sized rings making up the end pieces all originate from the same sized pipe but are split with some material removed and are then reduced in diameter with the aid of a heat gun. With the strainers I cut the mesh from the frame and molded it down to 90mm from its original 120mm by kneading with the fingers. ( I guess this means that you give up tea drinking, unless of course you have three strainers in the household.)
The internal assembly which holds the microphone consists of two pieces of pipe with rubber rings fitted at right angles. The mike is suspended at the point where the rubber rings cross. Check out picture 2 for detail.
The outer tube was cut from 90mm pipe and slotted at the bottom to fit the internal assembly (4). The end cap is held on with a couple of studs.(5) Maria sewed up a nice bag made from long haired fur bought from the local craft shop. I realized when the bag was on that there was no way of knowing which was front and rear. That's where the eyes come in! At the moment I am using my Shure SM 57 cardiod. A bit heavy after holding it up for a while so I will probably fit one of those shotguns later.
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But what happens when the wind is not coming from the west. Back in the studio, one of the problems facing those who want to get up close and intimate is that of pops. The pop, or plosive to give it the correct term, is caused by the sudden high velocity rush of air from the mouth when saying the letter 'P'.
Commercially made filters are available but I found one easy enough to make using household bits(14). The frame (12) is made from stiff steel wire soldered together. The split sleeve (13) is once again made from PVC pipe. (If you live in Perth you tend to accumulate lots of PVC pipe and fittings. 80% of gardens are reticulated from private bores so we are all amateur plumbers!)
To attach the frame to the sleeve I made a couple of lugs from steel sheet and soldered them to the wire. The gauze is a bit of nylon stocking. Results are great. I can huff and puff at the closeness which gives a warm and intimate sound and there is no popping.
Coming up in the near future is the amazing demountable voiceover booth. Room is at a premium here so a permanent booth is not practical.
- Yes, it's still coming! The Teleprompter project seems to have got in the way. The booth is up and running, just a matter of getting those all important pics and writing some script.