Lights and Sound: Fog Silencer?

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Fog Silencer?

Printed From: Community Theater Green Room
Category: Producing Theater
Forum Name: Lights and Sound
Forum Discription: Technical discussion
URL: http://www.communitytheater.org/forum/forum_posts.asp?TID=3460
Printed Date: 5/06/25 at 7:42am
Software Version: Web Wiz Forums 8.05 - http://www.webwizforums.com

Topic: Fog Silencer?

Posted By: kaelidancer
Subject: Fog Silencer?
Date Posted: 9/15/08 at 11:19am

This seems like a topic that should have been covered here before, because it's an issue I deal with every time I use a fog machine in a production... the awful, awful noise they make.

In this production, I have to use two of them... each mounted on a light tree on the back wall of the stage, shooting forward. All the sound comes from the muzzle, so I'm sure that one could construct a "silencer" out of some foam pipe insulation given enough space, but I don't have that sort of room back there. Is there a 6-inch solution to muffle the sound of a fog machine, without restricting the output?

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Kaeli Gardner
Johnson City Community Theatre
http://www.jcct.us - www.jcct.us
http://www.gardnerarts.com - www.gardnerarts.com

Replies:

Posted By: JoeMc
Date Posted: 9/15/08 at 12:47pm

The only thing I can think of, is an absorptive muffler, like a hot dog or a cherry bomb;- http://en.wikibooks.org/wiki/Image:Cherrybomb_muffler.jpg - http://en.wikibooks.org/wiki/Image:Cherrybomb_muffler.jpg

I have never tried it, but there would be no reason I can think of, why it wouldn't work. The Hot dogs are not that expensive, I have no idea bout the cost of Chery bombs?

Also they do make noise mufflers/silencers for Boilers & other steam vessels. You may be able to get one cheap at industrial salvage yard. However if you go to vehicle muffler outlet, they may have smaller hot Dogs, to suit motor bikes or smaller exhaust pipes.

The Hot dog like the Chery bomb is a straight thru muffler, so it would not restrict the fog flow - anyhow just a thought?

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[western] Gondawandaland
"Hear the light & see the sound!
TOI TOI CHOOKAS
{may you always play to a full house!}

Posted By: JoeMc
Date Posted: 9/16/08 at 12:05am

I was having a further think about this?

While I was having a bath last night & contemplating my left toe.

That it would be easy enough to construct a silencer, on the same bases as the hot dog/cherry bomb. From something like plastic water pipe or electrical conduit. As there is no heat involved, unlike an exhaust muffler.

Grab some Steel wool pot scourers, also one of those plastic net bags, that hold fruit, from the supermarket. Or even a synthetic bag women use to contain their bra's in a washing machine. [I'm sure they have a name, besides 'bra Bags' - but it is out side my technical understanding?]

Loosen up the steel wool pads & put them in to the net bag, so the wool strands are loose & bunched flat. Pull the bag thru the pipe, so it fits around the circumference of the pipe. Fold over the excess bag & gaffer tape it to the outside circumference of the pipe at both ends.

The diameter of the pipe should be large enough to accommodate the bag, with the loose bunched steel wool inside the walls of the pipe.

As with the muffler the noise should baffle & absorbed enough to reduce the sound dramatical.

You may have to play about with the length & quantity of steel wool. The net bag will hold the wool in place, however there may be a better alternative perforated inner tube material or item, that could be used?

El cheapo to make & fairly easy to muck about with, while tuning up the silencer.

I must try this one day!

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[western] Gondawandaland
"Hear the light & see the sound!
TOI TOI CHOOKAS
{may you always play to a full house!}

Posted By: kaelidancer
Date Posted: 9/16/08 at 10:41am

Good idea! I'll see what I can come up with :)

-------------
Kaeli Gardner
Johnson City Community Theatre
http://www.jcct.us - www.jcct.us
http://www.gardnerarts.com - www.gardnerarts.com

Posted By: JoeMc
Date Posted: 9/17/08 at 3:50am

One other thing you could look at, is using plastic drain pipe, the rectangular pipe may be an option, using the knobbly or dimpled foam. type used in a camera cases;- http://www.sunandski.com/ProductDetails.asp?ProductCode=9315062470825&Click=239&ci_src=10043468&ci_sku=9315062470825 - http://www.sunandski.com/ProductDetails.asp?ProductCode=9315062470825&Click=239&ci_src=10043468&ci_sku=9315062470825

The foam on the inside of the pipe, thats why a square pipe may be better?

Which would work much the same as when egg cartons are used, on the wall, as a sound proofing material.

-------------
[western] Gondawandaland
"Hear the light & see the sound!
TOI TOI CHOOKAS
{may you always play to a full house!}