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Brendan Marnell July 10th, 2008 12:30 PM

Improvise a muffler
 
I want to record the cries of gulls and gannets but I want to keep the sound of the wind to a minimum ... tomorrow!

Please tell me the simplest way to muffle wind noise/impact on ordinary XL2 mic. without losing the higher pitches of the seabirds?

Martin Catt July 11th, 2008 05:12 AM

Buy a chunk of fake fur from a craft store -- color doesn't matter, but get the fur that's at least 1" long. Make a closed-end tube with the furry side out that will just slip over the foam windscreen on the stock XL2 mic, Secure it over the mic with one of those double-sided hook-and-loop cable tie straps. Instant (and inexpensive) fur windscreen. I've used it in 30 MPH winds with perfect results.

I made one a few days after getting my XL2. Took maybe 15 minutes to make, all seams were hand-stitched, and the last inch of fur at the open end trimmed down to the cloth base for the hook-and-loop strap. I just leave it on the camera all the time, except when I'm using the wide-angle lens, where a few strands of fur make it into the corner of the frame. Got a secondary "booster" mic mount in the works to move it out of frame.

Martin

Brendan Marnell July 11th, 2008 09:37 AM

Thank you Martin. I am going to buy your clever furry idea, for free.

I'm just back from shooting gannets and puffins in a stiff breeze. A pair of nylon ankle socks were all I could think of (my wife did the thinking) and I have yet to download 50 mins to see what use if any they were.

Martin Catt July 11th, 2008 07:50 PM

Well, you could pull one sock over the mic, wrap some cotton batting or polyester stuffing around it, and then pull a second sock over the whole thing. The important thing is to have some dead air space surrounding the mic.

The furry cover gets some interesting remarks, mainly because it's blond fur with brown tips. It matches my beard. I think it has a little more class than the usual black furry covers.

Martin

Cole McDonald July 11th, 2008 08:44 PM

gutterscreen, wire to close, chopstix, hair binders and costume fur. attach to an old mike clamp that's been taken apart and voila!

http://yafiunderground.com/Images/blimp/mike1.jpg
http://yafiunderground.com/Images/blimp/mike2.jpg
http://yafiunderground.com/Images/blimp/mike3.jpg
http://yafiunderground.com/Images/blimp/mike4.jpg

Brendan Marnell July 12th, 2008 04:18 PM

That's hi-tech by my amateur standards Cole; it's encouraging to know that others are far ahead and involving the next generation. I have opted for a roll of cotton wool contained by ankle socks ... calling it a windsock just to confuse myself.

Cole McDonald July 12th, 2008 07:54 PM

I don't see problems... Um... I see solutions? OK, I just see geeky ways to find stuff to occupy my devilish hands ;)

J. Stephen McDonald July 12th, 2008 08:11 PM

These furry mike covers are known as "dead cat" windsocks. There's nothing like real fur to do the job right.

Added note: My cat helps me to work online and apparently reads English better than I thought, as he just went streaking out the door.

Martin Catt July 13th, 2008 05:58 PM

6 Attachment(s)
A few pictures might help. I got inspired today and finished the mic mount adapter to move the microphone about two inches up and an inch back to keep the fur out of the wide-angle frame.

First picture is the XL2 with the stock mic, home-made fur windscreen, and the mount adapter installed. Second picture is a closer look at the mic, windscreen, and adapter. Third shot is the mic and adapter removed from the camera. The fourth picture is the fur windscreen removed from the mic. The velcro strap is stitched to the windscreen so it doesn't get lost.

The fifth shot is the adapter, less than an hour out of the shop. It's made from 3/4" PVC water pipe, an electrical conduit clamp, two carriage bolts and nut, and a brass thumbnut I machined to clamp the mic in place. A couple sections of 5/8" vinyl hose are slipped over the conduit clamp arms to keep from scratching the mic. The white part is cut from a scrap of hi-density polyethylene block in the scrap box. This is the second version -- the first was a little too long and interfered with access to the microphone jacks.

Last picture is the adapter and mic mounted on the camera. Everything fits with no modification to the original mounts. No more blond fuzzy strands in the corner of the frame.

Next project is to make a mount for the Microtrack to go on my field mixer. One less loose piece of gear hanging off the cables.

Martin

J. Stephen McDonald July 13th, 2008 06:39 PM

Martin, your "dead cat" windsock rig is a gem. It looks simple, yet very solid and effective. In fact, a mike could be used on it without the windsock, if it wasn't needed, just to remove it farther from the camera. As you indicated, you could adapt this configuration to hold other attachments. Why doesn't Canon hire you to be an R&D advisor?

The only difference in one of these I might make, would be to use Kevlar instead of Polyethelene for the support pylon. Kevlar has an amazing characteristic to dampen sound and vibration and it can be obtained in solid blocks, like its chemical relative, Nylon. I have made mike support arms from multiple layers of Kevlar cloth and epoxy resin and they have completely removed camera operating noises from the soundtracks. I had thought that just moving the mike 8 inches from the camera would solve the problem, but there were still faint noises coming through when there was no ambient sound. After installing the Kevlar arm, these sounds disappeared, indicating that some of them had been traveling through the solid support made of ordinary materials. Although I prefer tape, the problem of operating noises does provide one more reason in favor of solid-state recording media.

The photo on the first link below, shows the Kevlar/epoxy arm, which has bends at each end and two mounting points.

http://farm4.static.flickr.com/3222/...dec888cf_o.jpg Maximize the page to see a larger picture.

Martin Catt July 13th, 2008 08:47 PM

I kinda "threw" it together using what was on hand. Polyethylene was easier to machine than aluminum, plus there was a perfect-sized scrap on top of the pile, so that's what I used. Total cash outlay for purchased parts was less than eight dollars, which includes some stuff I didn't use.

The only kevlar I've worked with was in laminates, and frankly I thought it was overrated. Certainly expensive. I lost autoclave access about fifteen years ago, so I don't do much carbon-fiber or prepreg work any more.

Despite comments I've heard from others here, I find the standard XL2 stock mic to be quite good. Haven't had any handling noise issues (yet). The stock isolation mount seems to work well, plus the adapter mount makes use of it, so there shouldn't be any difference. One of the problems with the first version of the mount was that in certain positions, the locking screw could tap against the camera frame, plus I made it extra-long because I wasn't quite sure where to position the mic. The "second" version just shortened the length of the 3/4" PVC pipe that mounts in the stock holder, and replaced a large wing nut at the back with an extra-thin 1/2" nut I cut down on the lathe.

I've already identified a lot of things that could be improved, and if I was going into production, I'd make the changes. This being a one-off item just for my own use, I'm pretty happy with it.

The one thing I've learned over the years in the various technical jobs I've had is to build your equipment solid and reliable. There's too much to worry about during a shoot without wondering if that gadget you jury-rigged together is going to fall apart today.

Martin

Sam Mendolia July 14th, 2008 11:29 AM

I totally agree with your last comment,

"The one thing I've learned over the years in the various technical jobs I've had is to build your equipment solid and reliable. There's too much to worry about during a shoot without wondering if that gadget you jury-rigged together is going to fall apart today."

I build most of my accessories, and test and make shure that nothing can go wrong.
I'm in a business that has many things that can go wrong, my job is to think ahead, and anticipate it and make shure it doesn't happen.

I'm an AV tech in a medical centre, by the way.

My latest gadget is an external power supply for my Canon Optura.

The power adaptor does what it is supposed to do.
But, with testing all the possible scenarios of carrying this rig around, I found the Canon plug is not designed to the "standard" jack, that you can pick up off the shelf at your local electronics supply. Less that 2mm, and the internal connection, the centre pin, does not make contact, on the jack, that you just bought.

I will have to get some material, and build myself one of these external mic holders, for my GL2, and then attach the mic to the external mic box, aka "beachtek", that I have been designing and building, over the last year.
I know it works, just thinking to much, on all the issues on this as well.

The material I have on hand is the same as what you used, for your holder, so, I will have to do my own "noise tests".

As you said, reliable and solid.

I love this place, lots of ideas, and more for me to play with.


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