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Discussion Starter #1 (Edited)
My small theater room is currently in the process of being rebuilt. Brick walls, a concrete ceiling, and wood floors translate to a room which rings like a bell. I've finally got some furniture in place and will be adding an area rug, but I also figured it might be useful to add a few acoustic panels to help absorb some of the wall reflections where possible. I looked at the options and found a number of how-to guides for building fabric covered panels, but that seemed a little boring. I then found a few sites that would print up movie poster style panels which seemed perfect. What didn't seem perfect was the $500+ asking price for each panel! I figured there had to be a better way, where "better" == "cheaper".

In short, an acoustic panel consists of a frame supporting the absorbing material wrapped in absorbing or transparent fabric. I'll cover each of these items separately, followed by a build log detailing the construction process.

Absorbing Material
The first order of business is some material to actually absorb the sound. There are plenty of guides for DIY panels around the internet, and the general consensus seems to be that Owens-Corning 703 glass fiber panels work pretty well. Roxul mineral board or mineral wool is another favorite. There are also plenty of lower-priced equivalent materials with similar specs from other companies. You can find this material online or check with a local insulation dealer. These materials are typically used for HVAC insulation, so you might find HVAC suppliers will carry what you're looking for as well. The standard size is 2' x 4'. In my case I had a local dealer which had JM 1000 panels in stock in the size I needed for $8 each out the door. As an aside - when I stopped by the local insulation shop looking for OC703 or equivalent, the guy I was talking to asked if I was making acoustic panels. Apparently I'm not the first person they've talked to about this kind of project! Anyway, don't be afraid to call up your local insulation guys - they do this stuff for a living and can be a great source of friendly experience.

Without going into too much detail, thicker material will absorb better across the spectrum and will also absorb lower. If you check the spec sheet linked above, you'll find the following table which illustrates this pretty clearly:

1 inch will be an absolute minimum and you can go up to 4" with most panels. In my case, the room is small already so hanging 4" panels on the wall is a non-starter. I went with 1½" material just for aesthetic purposes. 2" seems to be a common choice. If you're going with non-OC board for a lower price (and I suggest that you do), you're going to want something that's 3 lbs/cu foot or more.

Frame
The frame material will surround and support the fiber board and provide a rigid surface for stretching the printed fabric. Again, there are plenty of guides for creating a frame online. Otherwise, check local art supply stores for canvas stretcher bars. These are pre-cut materials used by artists for creating strong, square frames to mount ("stretch") canvas for hanging paintings and the like. They are dead simple to work with and can be assembled with few or no tools. The downside is that you don't often have a choice for how deep the frame will be to allow for 2" or greater material. Also, they can be expensive once everything is ordered. If you haven't figured this out by now, I'm cheap, so I made my own. I chose to rip a 2x4" to create 1¼" bars then tacked on ¼" quarter-round shoe molding to create a 1½" deep frame. Total wood cost for the four 1'x3' frames was $15.

Art
Finally, you need the printed poster! For this you are going to need two things: some source artwork, and somebody to print it on fabric. You can find source art all over the internet. If you don't mind spending a couple dollars this can be a good source. Otherwise, google image search can be helpful. You are going to be blowing this up to poster size so you are going to need high-resolution images to start with. Anything under 1000-2000 pixels high is probably not going to look too good. In my case, I selected a series of four posters from the movie Goldfinger, blew them up a bit with third party software, then touched up the final results to smooth out the resulting image (having a professional photographer wife helps with these steps).

Next, you need to get this printed. There are loads of shops that offer digital canvas printing - you don't want this! Canvas prints are great for art reproduction, but are very thick and won't transmit sound to the material inside at all. What you want is printed fabric. Your options may vary depending on where you are, but I found Spoonflower in the US and they are great! They have a variety of fabrics, a super-easy to use website, and can print large-format fabrics for cheap. The site also allows you to share posters you've uploaded. You can find mine here and here. You can order a fabric sample set from them to get an idea of what the options are. The fabric needs to be thin enough to transmit sound while still being thick enough to allow a decent print. You'll want to stay away from stretchable materials as they will be nearly impossible to mount. After reviewing the sample set then ordering a couple printed samples, I've found that the standard "quilting weight" fabric offers the best balance between print density and acoustic transparency. [update: mtbdudex is a stud and tested the Spoonflower "Quilting Weight" fabric for acoustic transparency here. Short version - it works great!] My order for the 4 posters came to $36 shipped and arrived in about 2 weeks with standard shipping.

After additional materials (some adhesives, fasteners, etc), this whole endeavor added up to just under $80 for 4 panels. That's more my price!

Full length view of 4 completed panels


Corner detail



Build Process
First - a disclaimer. This isn't intended to be a "how to", rather it's more of a build log of how I made my first panels. My woodworking skills would charitably be described as "novice". Feel free to adapt and improve upon what you see here, and don't assume that just because I'm doing it one way that you shouldn't do it another.

The first step is to build out the frame. I'll be making the remaining three panels which are 1'x3' each. I'm starting with a few lengths of 2x4 that I bought from HD because they were cheap. I then ripped them down to 1¼" square for the body of the frame. You can likely find pre-cut pieces to fit your project at the local lumber yard, or you might get them to cut the pieces for you.


I then tacked a ¼" shoe molding to the bars to create the stretcher bar. The idea is to create a narrow point of contact around the edge for the fabric so the wood frame underneath doesn't show through as much. For whatever reason this method doesn't appear in any of the DIY panel guides I've read, nor is it used for any of the (mostly overpriced) DIY "kits" for making your own panels. I don't know why this is - in the art world you simply don't stretch a canvas over a frame without doing something similar. Here is an end view of the pieces before cutting, and a shot of the molding being tacked to the frame. I've highlighted the outline in red to give you a better view of the profile. I'm using a brad nailer here, but you can use a regular hammer and nails if you want. Just make sure to use small nails (brads) to keep from splitting the wood.


Once the molding is attached, use a miter saw to cut the pieces to length. You can get a cheap miter box from your local hardware store for $10-$20 if you don't have one. I'd really recommend against just cutting this by hand without either a miter box or chop saw or similar - you're going to want these cuts to be 45° on the nose. Here's a look at the cutting process, along with the finished edge and finally the parts for 3 complete frames (six 3' pieces and six 1' pieces).


Next you need to assemble the frame. Some corner clamps help here, or just use a square edge and some normal clamps. Run some wood glue along the inside mating surfaces in the corner, then tack each corner with nails or counter-sunk screws. Once these are together, sand them down so the outside edges are smooth. If necessary, throw some wood filler in any gaps you might have. It doesn't have to be pretty, just relatively uniform in color without any gaps or uneven edges.




For these next few steps I'm going to be handling the bare fiberglass. This is nasty stuff, something a trip to the urgent care clinic taught me at a very young age. At a bare minimum, wear long sleeves, gloves, eye protection, and a dust mask. You really don't want this in your lungs or eyes (trust me on this), and it's irritating on your skin too. Do not screw around here - the gear is cheap.


First you need to cut the panel. Here I've laid my frame on top of the piece of fiberglass and used a marker to mark the edges. You can then use a box cutter or similar to cut through the panel. Once it's cut it should fit relatively snug inside the frame.


Once the panel is fit into the frame you might want to take the additional step of using an adhesive to make sure it stays put. I've run a bead of Liquid Nails along the edge and then smoothed it down with a disposable brush. I'm using the "projects" type as it's easy to work with and happens to match the color fairly well so it won't be visible afterwards.


Finally it's time to get the print stapled to the frame. First, make sure the work is ready to mount by ironing out any wrinkles. If it's dirty for whatever reason, run it through the wash. Remember - this is fabric intended for use with clothing, so ironing and washing is OK! Once the art is ready, center the piece on the frame and tack it in the middle of each edge. You'll be working from the back (still with gloves!), so it might take a couple tries to get it lined up perfectly. Don't be afraid to pull staples and try again if needed.


Now work your way out from the center of each edge. Once you get to the corners, you will need to square off the corners like a bedsheet. I've kept the folds on the top and bottom of the frame as those will likely be less visible than the sides.


Once you've got the entire piece stapled, you are going to want to add some sort of backing material to keep the fiberglass from getting into the air in your room. I simply used an old white bed sheet, you can use whatever you might have lying about the house. The color and condition shouldn't really matter as nobody is going to see it anyway.


After everything is stapled, you'll probably still have a few minor wrinkles. I've found wrinkle releaser from your local grocery will work wonders. Just spray the final panel down with this stuff and the wrinkles will pretty well disappear. Now add a sawtooth picture hanger, hanging wire, cleats, or whatever works best on your wall to get it mounted. I used a sawtooth hanger because I'm mounting to a rough brick wall which prevents me from any chance of actually firmly mounting these panels. You might find using a simple cleat will provide a stable solution to mount to more traditional walls.

Once it's mounted, you are then ready for the final and most important step - taking pictures and posting them here!
 

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Great article! Do you have any intentions of ceiling treatment? I have been pondering several ideas but more ideas from others are always helpful.
 

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Discussion Starter #3
Great article! Do you have any intentions of ceiling treatment? I have been pondering several ideas but more ideas from others are always helpful.
That is a whole separate project! The trouble is that I'm still dealing with my condo developer regarding an occasional leak in that ceiling, so I'm not doing anything there until the issue is fully resolved. What I'm really hoping to do is a starfield ceiling which will be quite an undertaking itself.
 

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VERY nice.... I am liking this DIY article, and will be following for sure, please accept my eventual plagurization of your method as a compliment for how well it works! I shall call them "LumaPanels"
 

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VERY nice.... I am liking this DIY article, and will be following for sure, please accept my eventual plagurization of your method as a compliment for how well it works! I shall call them "LumaPanels"
Well for that you're going to need to pay my license fee - pictures!
 

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So you are just filling the backside with OC703?

Also, I know it sounds odd (i'm no expert on fabric work) but which way on that wood frame does the fabric wrap? Rounded edge out? up? Behind?

Sounds like a good arts and crafts job for my wife -- considering she wants to help out but isn't very good with a table saw ;)

I ordered a single panel from them to test and play with -- $20 is a STEAL For fabric that's printed like this, I cannot wait to see the results, i'm months away from needing it, but couldn't wait to try it!
 

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Luma - I see you are on HTS as well as AVS http://www.avsforum.com/avs-vb/showthread.php?p=20036196#post20036196

For people here @ HTS, based on this great find by Luma, I'll be ordering 8" x 8" test samples and conduct a nearfield speaker test without and with the material, and compare the frequency change.

I like objective data to back up subjective / gut feel for the fabrics acoustic transparency relative to mid-hi frequency.

Their website is pretty simple to use, after correctly sizing them to 8x8 and 150dpi in CS5, I've uploaded images for my test swatches, will add a few more tonight and order the samples.
Once I get them will be a Engineer geek and take measurements and share results, and judge their process ability to print photographic quality images not just poster type images.

I did this while speaking with Steve B again, great customer support.
[/QUOTE]
 

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Discussion Starter #9
So you are just filling the backside with OC703?

Also, I know it sounds odd (i'm no expert on fabric work) but which way on that wood frame does the fabric wrap? Rounded edge out? up? Behind?

Sounds like a good arts and crafts job for my wife -- considering she wants to help out but isn't very good with a table saw ;)

I ordered a single panel from them to test and play with -- $20 is a STEAL For fabric that's printed like this, I cannot wait to see the results, i'm months away from needing it, but couldn't wait to try it!
The frame itself pretty much just acts as a rigid support for wrapping the fabric and holding the 703 (or similar) in the middle. It will make more sense once I complete the rest of the pictures (just finished installing a new floor yesterday, got a sofa being delivered today, excuses, excuses), but in general, the flat edge of the quarter-round will be at the exterior of the frame. Here's an mspaint cross-section of the frame to illustrate:



The fabric is in red, and the top of the picture is the front of the frame. The idea is to minimize contact between the fabric and the frame at the front in order to prevent you from being able to see the frame through the material. My first run was marginally successful at this, the next three will probably have a thin layer of batting placed in there too. If you look at the pictures above, you can still see the internal outline of the frame from the front, which isn't as bad as the flash makes it look and really isn't noticeable in the room, but I think I can do better.
 

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Or use a more specific print that covers the frame -- or paint the frame black -- creating a border.. Lots of options there...

I understand where you are going with that -- but where is the insulated panel going to go?

I figured you were going to go, print, insulated panel, wood frame -- and then wrap the print around the insulated panel and then staples to the frame -- the way others have done it in the past.. just ensure the print you order has enough blank fabric to stretch around.
 

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I uploaded 8 more images and placed my order for the 8" x 8" printed samples with my pictures/designs on them.
It will take 10 days (week of March 7th ), once I get them I'll run my acoustic tests and share.
Here are the 8 more images, for a total of 14 in my sampler pack.
These are more colorful, should give a good indication of their color ability.
 

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This is an outstanding DIY.:clap: Thank you so much for the detailed information and pictures. I will be doing the same and will most likely buy the artwork from the link you provided. Is there a guideline for the resolution to size? (eg. 492 x 980 ok up to 12" x 24" etc.)
 

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I then tacked a ¼" shoe molding to the bars to create the stretcher bar. The idea is to create a narrow point of contact around the edge for the fabric so the wood frame underneath doesn't show through as much.
You could save some steps and parts by simply bevel-cutting when ripping the 2 x 4 . . .
just put the table saw blade at maybe 10 deg off. A quick rounding with sandpaper (you don't want a soft knife-edge) and you're ready to make completed frames. Assemble with the high edge on the perimeter, and the face of the frame slopes slightly inward - low edge will be the one touching the fiberglass.

Aside: The downside of framed panels is that some absorption is lost, particularly with smaller panels, due to loss of the exposed edge. This "edge effect" is what makes it possible for some materials to have greater absorption coefficients than the theoretical maximum of 1.00. Note that the midrange and treble absorption shown in the table above seems to be related to thickness. Thicker panels have more total surafce area. 4" OC 703 in a frame will tend to have maximum values of 1.00, rather than the data shown.

None of this is "bad"; just something to be aware of if you are calculating the number of panels you need based on the data for "naked" fiberglass.:rubeyes:

'nuther Aside: Any fabric you can easily blow through and that lets pinpoints of light through when held up to light is plenty acoustically transparent. There are even some 'heavy' fabrics that pass this test (and some thin ones that don't). Don't be concerned if a fabric doesn't pass very high frequencies -- they are likely absorbed, rather than being "blocked" (reflected) by the fabric. This would only be a concern for grille cloth. Also note, very few treated rooms have too many highs left, the opposite is almost always the case.

-- Mark
 

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You could save some steps and parts by simply bevel-cutting when ripping the 2 x 4 . . .
just put the table saw blade at maybe 10 deg off. A quick rounding with sandpaper (you don't want a soft knife-edge) and you're ready to make completed frames. Assemble with the high edge on the perimeter, and the face of the frame slopes slightly inward - low edge will be the one touching the fiberglass.

Aside: The downside of framed panels is that some absorption is lost, particularly with smaller panels, due to loss of the exposed edge. This "edge effect" is what makes it possible for some materials to have greater absorption coefficients than the theoretical maximum of 1.00. Note that the midrange and treble absorption shown in the table above seems to be related to thickness. Thicker panels have more total surafce area. 4" OC 703 in a frame will tend to have maximum values of 1.00, rather than the data shown.

None of this is "bad"; just something to be aware of if you are calculating the number of panels you need based on the data for "naked" fiberglass.:rubeyes:

'nuther Aside: Any fabric you can easily blow through and that lets pinpoints of light through when held up to light is plenty acoustically transparent. There are even some 'heavy' fabrics that pass this test (and some thin ones that don't). Don't be concerned if a fabric doesn't pass very high frequencies -- they are likely absorbed, rather than being "blocked" (reflected) by the fabric. This would only be a concern for grille cloth. Also note, very few treated rooms have too many highs left, the opposite is almost always the case.

-- Mark
Good call on all accounts!

In regards to the "naked" fiberglass - I chose to use a frame to give a more square, defined edge to the resulting panel. I would imagine using a more rigid board (Roxul maybe?) might be fine without a frame.

In regards to the testing - I came to the same conclusion. Testing for transmission doesn't account for absorption by the material itself. The only test one might hope to do is to test for reflection, which might be hard to accurately gauge.
 

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Try This!

. . . I came to the same conclusion. Testing for transmission doesn't account for absorption by the material itself. The only test one might hope to do is to test for reflection, which might be hard to accurately gauge.
Yep, reflectivity is pretty tedious to measure accurately. To do it right, 1) an anechoic environment is needed, and 2) reflectivity changes with angle of incidence.

Having said that, one can learn a lot with my totally subjective (but useful) layman's test:
Get a piece of plywood or MDF at least 2' square. Go outdoors away from all structures and noise. Make sure neighbors or stangers are watching from afar ( Optional ). Hold the board in front of thyself and hiss loudly and consistently at it. Put a lot of sssssibilance in it. This is the Poor-Man's White-Noise Generator (PMWNG). Try at various angles and distances, listen carefully, get familiar with the sound.** Do the same with your cloth wrapped on it. A-B several times and just listen. Whatever change you might hear is the absorption by the fabric itself.

For the reverse, repeat the procedure using your absorber material instead of the board. You can find out if a cloth is particularly reflective. For giggles, substitute a sheet of saran-wrap, a plastic trash bag, etc for the cloth. Refer to the blank board as needed to recall what fully reflective sounds like.

Using these two simple tests, you can meaningfully determine the sound reflective/absorptive/blocking/transparency behavior of any material. The perfect Grille cloth should, for example, present NO change in both of the tests. A decent absorber fabric will present no change in the second test, but can vary from absorptive to transparent (no change) in the first test.

** This is also a fantastic way to learn about comb-filtering. Move the board closer or farther from your PMWNG and listen. Once you really learn how to recognize it, you'll start to notice it in real-world listening situations. Double-edged sword . . .

Whew... sorry for the sidetrack:coocoo: -- this should prob have been under a new thread.

-- Mark
 

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Ha Ha Ha! That awesome Mark! The bright side is you'll never have to worry about those pesky trick or treaters again! Two birds with one stone. I'm doing it every night for the next week just to make sure they all see--and on my front porch to boot. Maybe if I do it enough, the neighbor's cat will find a new yard to relieve herself.

Dan
 

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I am STILL waiting for my test print to show up from them. Shipped out March 4th - and it's still not here.. (Canada)

Can't wait to test it out.

Your new photos don't show the detail on the top side as much - so the print is stretched around the wooden frame at the front? This isn't ideal as you want the front and sides to be insulation and not wood (but I am sure it still makes a huge difference)
 

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Well my test print showed up today....

WOW is all I can say -- the quality of the print is OUTSTANDING. Not sure if I ordered exactly right - but for testing it's perfect, I am so very happy at the print quality - I might order from these guys more often for other stuff..
 

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I've been looking all over for a good source for custom printed fabric. Just picked up a pack of 6lbs mineral fiber for $5/board. Am going to seriously look into getting some fabric from SpoonFlower. Do you know if they are strict on copyright laws (ie: refusing to copy a poster, etc).

One question though. Instead of using the quarter round on the face would it not be better to angle cut with a table saw the side of the 1x3 to create a beveled inside edge? Also would it really be that important when using 1x3's since the edge would only be ¾".
 
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