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Discussion Starter #1
What is the maximum thickness of plastic used to wrap oc 703 for absorption panels? I want to put plastic for any health reasons. I am using stretch velvet mostly for absorption panels, not sure its effectiveness. For bass traps, I plan to use 6 mil plastic. Appreciate anybody can share their experience.
 

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The thickness is really only going to matter in regards to the ease of installation. I would purchase the heaviest "drop cloth" plastic and go with it. The high and mid frequencies are going to be reflected by any non-breathable material. But the the sub-sonic ferquencies will travel right through it. Whether you use heavy paper or plastic is indifferent (in the grand scheme of things). Now saying that, some folks want or even need a broadband absorber instead of just a bass frequency trap. In that case, unfaced/un-wrapped, bass traps and/or panels are better.


On a separate issue, you should concider 1 build or a bass trap / absorber thread for ALL your questions instead of starting a brand new thread for every question.
 

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Discussion Starter #3

Quote:
Originally Posted by BroncoSport  /t/1421341/maximum-thickness-of-plastic-used-to-wrap-oc-703-for-absorption-panels#post_22240415


The high and mid frequencies are going to be reflected by any non-breathable material. But the the sub-sonic ferquencies will travel right through it. Whether you use heavy paper or plastic is indifferent (in the grand scheme of things). Now saying that, some folks want or even need a broadband absorber instead of just a bass frequency trap. In that case, unfaced/un-wrapped, bass traps and/or panels are better.

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Thanks. You said non breathable meterial will refelect. Why can't people use breathable material instead of unfaced/unwrapped. Is there nothing that is breathable?
 

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I guess I'm not following you. Any hard or NON porous surface will reflect high and mid frequencies. Sub sonic frequencies will go right through those same surfaces, but without a huge amount of thickness it wont affect the bass frequencies much either (meaning the standard 1" panels) . The only real block for the lower frequencies is MASS. Regular insulation doesn't really absorb all the low frequencies, just dampens and slows it down before it hits the wall behind the insulation and then reflects back into the room to be "slowed down" and attenuated again by the same insulation.


Instead of wrapping with plastic or paper, I utilized faced insulation (saved a step) for my bass traps in the front corners. If I deem it to be too much reflection on the high end, I will stand up some of the left over IS300 rigid 1" insulation I have left after the build in front of them.


There are many ways to go about taming bass, but all seem to be very similar for the DIY crowd. Do a search for bass traps and spend some time reading the threads around here.


For non-bass traps, any wrapping of the fiberglass with plastic is going to negate the absorbtion of the high/mid frequencies you want. As far as health concerns, after you wrap the insulation with fabric stop brushing against it, it will NOT introduce fibers into the air. It's just a pain during the initial handling. Gloves, long sleeved shirt and a mask might be in order for you. Also, a large shop vac with the hose removed makes for a decent air filter during this process!
 

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Discussion Starter #5

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Originally Posted by BroncoSport  /t/1421341/maximum-thickness-of-plastic-used-to-wrap-oc-703-for-absorption-panels#post_22241724


Regular insulation doesn't really absorb all the low frequencies, just dampens and slows it down before it hits the wall behind the insulation and then reflects back into the room to be "slowed down" and attenuated again by the same insulation.

Instead of wrapping with plastic or paper, I utilized faced insulation (saved a step) for my bass traps in the front corners. If I deem it to be too much reflection on the high end, I will stand up some of the left over IS300 rigid 1" insulation I have left after the build in front of them.
It is good to know that after building bass traps, I can place absorbers for high frequnecy when needed. Thanks for sharing.
 

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Discussion Starter #6
I am planning to construct bass trap like this which my friend created few days back. He is using 8 feet metal corner breed from home depot to make frame for either bass trap or for absorption panels. Since it is light weight, it is easy to move. The one shown here is for the back. Since, dipolar speakers are on the wall, he put small metal sheet facing surround speakers to reflect high frequency content. At the end of it he wrapped in 6mil plastic paper and then cloth stapled. Do you have any feeback/concerns to do like this?



 

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Discussion Starter #8

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Originally Posted by BIGmouthinDC  /t/1421341/maximum-thickness-of-plastic-used-to-wrap-oc-703-for-absorption-panels#post_22245078


The sheet metal might rattle
Thanks for reply. I never thought about rattle. If needed I may use knauf paper wherever it points to surround speaker. Do you think knauf paper needed or 4 mil plastic is enough?


Also, do you have any comments on metal bead as frame? Do you think same problem ? Following is used.

http://www.homedepot.com/buy/building-materials/drywall/gibraltar-industries/cornerbead-1-14-in-x-10-ft-galvanized-21030.html
 

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Discussion Starter #10

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Originally Posted by Dennis Erskine  /t/1421341/maximum-thickness-of-plastic-used-to-wrap-oc-703-for-absorption-panels#post_22245127


The metal is not a good idea. I'd suggest you use 3 mil plastic sheeting

Thanks Dennis. I am planning to wrap whole bass trap in 4mil plastic wrap that I bought from home depot. So, plastic wrap itself acts as reflection, so there is no problem if surround speaker is pointing to bass trap. Am I right?


I intended to use metal bead as frame. I guess I may loose little space as metal is on top of OC 703 .I am hoping it is insignificant.


I also bought .3mil plastic to wrap for 2 or 4 inch OC 703 absorption panels. Do you think even .3 mil plastic wrap defeats purpose of absorbing high frequncy content? Thanks for your help.
 

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Discussion Starter #11
I have these two questions.


1. I have vaulted ceiling. It is 9 feet room but 8 feet at the walls. When I build corner super chunk bass traps, is it really important to go all the way to 9 feet or it is not significant to go up to 8 feet. It is little more work.


2. From corner to corner bass traps that are going to lay on the floor what shape is recommenced?
 
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