I got a few PM's today about my DIY traps today and I figured since they are so easy to make I figured I would post a few pics on what I did with pictures to help whoever wants to make some out.
First off find someone who will sell you OC703 or OC705, keep in mind the latter will be more absorptive, it is generally sold in sheets that are 4'x2'x2" or 1" thick sheets. One note: be sure to always wear gloves and if you can a mask with the fiberglass for your protection. I used 2" thick sections for reflection absorption and 4" thickness for corner straddling to help the low end. With this build you can save yourself money and get added benefit by making the frame a little deeper than the used material. This allows some waves to go through the dampening material then reflect off the wall to be absorbed by the back side of the dampening effectively doubling the working size of your dampening material. Because of this the reflective portions of my panels where a total of 4" thick and the bass traps were 6" thick. If you don't want your frames sitting that far off the wall you don't have to do this.
The first thing you need to do is decide on the size of panels you want to have. I went with a variety of sizes. The easiest way to do this would be use the original 2'x4' sheets, but if you want to cut the material be sure to wear a mask and I would recommend using a serrated knife with a guide on each side so you cut straight.
Here are my cut pieces:
As you can see there is also a frame for one of the bass traps in this picture. First what I did was glue to pieces of OC705 together using 3m spray glue. After that I made the frame while the fiberglass dried. I made the frames slightly smaller than the cuts of fiberglass to ensure that the fiberglass would not sag or slide out accidentally.
When making the frame just but some 1"x4' planks and cut to size. If you do not have a saw your local hardware store will likely make cuts for you at a minimal price. Although, if you are more handy you can do what I did and buy a sheet of plywood and cut the pieces to size which will cost less, but be considerable more work. To get a clean look I used countersinks to hide the screw holes. I used two screws per corner and filled with a liberal amount of wood glue before tightening with a drill. While this frame doesn't look sturdy it is very much so and I haven't had a problem with them at all.
To get the fiberglass in the frame I needed to coerce the fiberglass in without breaking it too much to do this I wrapped a corner in plastic wrap and used the plastic as 'lubricant' to get the OC705 in easily:
Once you have your fiberglass in the frames all that is left is covering them with cloth. All you will need for this is a staple gun and cloth. When picking your cloth out I would recommend going to your local fabric store and buying a fabric that you can breathe through easily. If you feel your breath, fairly undisturbed, it should allow sound waves through as well.
Cut the fabric larger than the face including the sides of the frame and some of the back as well. It is far easier to cut a larger piece than a smaller one when stretching fabric.
To start out ensure the piece of fabric is large enough and then put one staple on the back center of one part of the frame. Stretching the fabric evenly to the opposing side put a staple there. Then do the same with both other sides of the frame. After this slowly staple outwards evenly on all sides trying to keep the fabric stretched evenly all around.
In the following picture I started with the top portion and stapled center then went to the bottom stapled center. After that I put a staple in the center of each side and then started over adding a two or three staples per side always going to alternating sides and ensuring that there were no wrinkles in the fabric.
Some of the finished pieces:
The only blemish you can find on these which can be fixed by more careful folding of the cloth:
To hang these I bought eye-hole screws and screwed them in the back using picture wire between them. After that I used a heavy weight picture hook to hang these followed by foam on parts that touched the wall if I felt decoupling was needed.
If you have any questions feel free to ask here or PM me.
Edit: For more information on acoustics I can recommend
this website link or this
book.