These panels are orders-of-magnitude better than any commercial sound-dampening product. They also look great and are inexpensive to make!

Supplies

MATERIALS

Scrap wood for the frame (I used wood from a shipping pallet)
Hardboard or Thin Plywood for the backer board - 1/4" thickness is ideal.
Thin OBS board (1/8" thin if you can find material that thin)
Navy Blue Hand Towels (6 hand-towels) https://amzn.to/2QkjvnC
Old bath towels (they can look ugly because nobody will see them... just ensure they're clean)
Wood Glue (Titebond 2) https://amzn.to/3goeODC
Acrylic Primer https://amzn.to/2Qg9IPt
Acrylic Paint (I got a small bucket at Home Depot... choose a color you like) I chose: Behr light blue, color code: S4602u
Framed artwork sawtooth hangers https://amzn.to/3j5dO9p
Painters tape (to act as a clamp while the glue dries)

TOOLS

Table Saw
Benchtop Belt Sander or some other way to sand
Benchtop Disc Sander
Bandsaw and/or Scroll Saw and/or Jig Saw.
Router table (any brand... but I love my Kreg brand) https://amzn.to/2Ev3bxs
Router for router table (any brand... but I love my Triton) https://amzn.to/31lVumd
Adjustable-Depth Router Rabbeting Bit https://amzn.to/2EadgAr
Small paint roller/pan combo https://www.homedepot.com/p/Shur-Line-3-in-Trim-a...
Point Driver (optional... you could just glue the baker permanently to the frame... but, these Point-Drivers are so cool!) https://amzn.to/34wXxGp
Pencil
Scissors
Staple Gun/Staples

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Step 1: Rip Boards to Width

Rip the boards that will be used for the frame on a table saw.

Use several passes to ensure both of the long sides are parallel.

The final width should be 2.25 inches.

Step 2: Cut Boards to Length

Set your table saw blade to create a 30º angle. (see photo)

Use the table saw's miter gauge to cut the boards to the proper length: 7.5 inches.

Use a pencil to mark the location of the first board so you can make accurate repeatable cuts. It's important that each board is the exact same length.

You'll need 6 pieces per hexagon because hexagons have six sides.

SAFETY TIP: Never place the workpiece under the blade. Notice the position of my hands and the workpiece in the photo... that's the proper orientation because you will be much safer on this side of the blade. The blade can much more easily cut you on the other side and unexpected things can happen to smaller pieces of cut-off material when you're on the wrong side. The last thing you want is to be startled by the cut-off piece doing crazy things when your hands are so close to the spinning blade that is tilted toward your hands.

Step 3: Glue Frame

Use wood glue to assemble the frame.

If your cuts are exactly 30º and each frame piece is exactly the same length, your hexagon will come together perfectly.

Wood glue is all you need and will be plenty strong enough. Use painters tape to hold the frame together while the glue dries.

Step 4: Create a Rabbet

Use a router table with a rabbeting bit to create a step-shaped recess cut along the inner edge of the frame.

This rabbet will be in the back of the frame and be used to secure a backer-board.

The amount of material should you remove (aka: the height the router bit should be above the router table surface) should be the thickness of the backer board plus the thickness of any picture-hanging hardware. I use the sawtooth-type hangers and they're about 1/8" tall. If the plywood backer is 1/4" thick the router bit should be 3/8" above the table's surface. It may be best to give yourself a little bit of extra space... so in this instance, 7/16" would be ideal. Again, measure your materials and set the router bit height as needed.

SAFETY TIP: Hold onto the workpiece with a firm grip and be sure to keep your fingers away from the blade. Never move the workpiece in a direction that will cause a "climb cut" because that can violently shift the workpiece causing your hands/fingers to touch the spinning bit... and that would be very painful for you.

Step 5: Paint Frame

Paint or stain as desired.

I used primer from a spray can. Then used a roller to apply indoor paint.

Step 6: Cut Backer Board

Place the hexagon frame on a thin piece of plywood and trace the inside edge with a pencil.

The plywood should be thin. 1/4" is desired but 3/8" will also be acceptable. You could also use hardboard or MDF rather than plywood. Nobody will see the backer board so the material really doesn't matter. The thinner this board is, the better it will be because it will allow you to use thicker strips of sound-absorbing towels.

Cut the hexagon shape you drew on the plywood close to the line (but not on the line). You can use any tool, or tools, for this. I used a scroll saw and a bandsaw. You could also use a hand-held jigsaw.

Use a disc sander to remove material right up to the pencil line. Test fit occasionally. When the back fits inside the rabbet nice and snug you are done with this step.

Step 7: Install Exterior Fabric

Cut thin pieces of MDF (1/8" thick) into 1" strips about 5 inches long.

Use the frame as a guide and cut the exterior fabric into the asterisk shape shown in the photo.

Place the MDF strips over the fabric. The MDF strip should be placed directly above the outer edge of the frame. Don't overhang it. Don't inset it. This will keep the exterior fabric exactly on the edge of the frame.

Use a staple gun to fasten the exterior fabric to the frame.

Do this for all six sides and choose the opposite side next. (like you're reattaching a tire to your car). Pull the fabric tight... but not too tight. Just medium-tight is desired.

You're almost done!

Step 8: Cut and Install Interior Towels

Measure the width of the frame from the front to the start of the rabbet notch.

This measurement is the width you must cut the towel into strips. Simply use a pair of scissors. You'll need about one towel per hexagon.

Gently lay the strip inside the hexagon as shown. Fill the entire cavity. Do not compress the towel. Leave it fluffy. Fluffy is the best for sound absorption.

Step 9: Secure the Backer Board

Add picture hanging hardware. I used a sawtooth-type hanger. I also used 2-part epoxy but frankly, that isn't needed.

Use a point-driver tool to secure the backer board. A low-cost alternative would be to simply use wood glue to permanently attach the backer board. The point driver method allows you to remove the back but frankly, that should never be necessary.

Hang your new soundproofing hexagon on the wall as you would any other piece of framed artwork. It should sit flush with the wall... which is a nice professional look.

Be sure to scream and yell so you can fully enjoy the minimal sound reflections your awesome new hexagons will provide!