# DIY Acoustic panels/spray adhesive



## jmmdm2 (Mar 3, 2009)

I've decided to make my own acoustic panels so I ordered a few things last night. 

6 panels OC703 24 x 48 x 2 inch

3 panels OC703 24 x 48 x 4 inch

10 yards black burlap and some misc fasteners.

I noticed that they also sold spray adhesive but I'm not sure if that's the way I want to go. I don't know how to coat the panel with the adhesive... do you coat the entire face of the panel? The sides and back leaving the front open for sound to travel in and out? Does the adhesive effect the properties of the acoustic material?

I came to the conclusion that I would simply build a frame for the panels and stretch/staple the fabric around the back of the panel without using any adhesive at all.

I'm trying to understand how the spray adhesive effects the panel, has anyone gone this route? Should I stick with the wood frames or try the adhesive?


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## bpape (Sep 14, 2006)

If you're going to frame them, no adhesive is needed. IMO, framing is almost a must with 703. Getting the fabric tight enough to look decent will crush the corners if not framed.

Bryan


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## bpape (Sep 14, 2006)

If you're going to frame them, no adhesive is needed. IMO, framing is almost a must with 703. Getting the fabric tight enough to look decent will crush the corners if not framed.

Bryan


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## jmmdm2 (Mar 3, 2009)

I understand, just wondering if the adhesive would impact the sound absorbtion IF I didn't frame them and used the cloth only. Good info about stretching though, I wouldn't have known it needed to be that tight.

I have to upload a picture of my front wall progress. There's lots of places that are going to be an issue. I see lots of HT builds here that actually treat the entire front wall and so far, mine has nothing but birch plywood to reflect sound. Must be killing the overall image.

  

I will be placing a 24 x 48 x 4 panel of OC703 under the TV and maybe an inch or two off the wall. Just to the sides of the false TV wall are the inserts I made to allow access to the rear of the system. These inserts have a pocket that could hold a 4" thick piece of OC703 with two inches of dead air behind it. There's also room to add 24 x 24 panels directly behind the mains in either 2" or 4" OC703 and there's a spot on the front face of the rack for more panels (custom cut).

Seems I also need a nice center channel stand.


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## K Shep (Jan 30, 2010)

I have not read anywhere that the adhesive affects the absorption value of a panel. I purchased 3M Super 77 spray adhesive for my OC 703 build. I have photos of the process, once I figure out how to load photos I will.


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## jmmdm2 (Mar 3, 2009)

I'm very curious to see your panels. Are you having trouble uploading to this site? I recall a how-to somewhere around here. I still don't have it figured out, I go in through usercp and find the uploader that way.


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## bpape (Sep 14, 2006)

There may be a minor impact on high frequency absorption. Might be less than the cloth on top of it is imparting though. A lot of variables here. As long as you're judicious with it, it should be fine.

BTW, the front wall should be as completely dead as possible in a multi-channel setup. The reason is to prevent reflections from the surround channels from contaminating the front soundstage. It can also be helpful for dealing with SBIR when speakers are too close to a boundary - though obviously an entire wall is not necessary for that - only behind the speakers.

Bryan


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## Chester (Feb 19, 2007)

Probably would have to do with how much of a 'hard shell' layer is created by the adhesive... maybe rubber cement or something similar would be a good thing to experiment with since it never really gets crusty in my experience.


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## mattw (Oct 1, 2009)

For my absorbers I used only a backing frame and 3M General Purpose 45 adhesive to adhere the fiberglass sheets to each other (1" sheets) and to adhere a sheet of Kraft paper on the front. I used just the bare amount to keep everything from scooting around and am fairly confident it has little to no effect on the frequencies it absorbs.


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