Introduction: Skyline Sound Diffuser - Wall Art

About: Hi there! My name is Bob and I am passionate about woodworking and teaching. I have been teaching woodworking to adults for several years, and I also make videos for my YouTube channel Bob's Wood Stuff. I put…

Hi there! In this project I will show how to build this nice-looking skyline style sound diffuser out of wood. This type of sound diffuser does not absorb the sound, but instead randomizes the shape of the echo to create a more natural sound. I mostly use it as wall art, but it does provide some sound improvement for recording in that room.

This project is simple to make.

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(Supplies links are Amazon affiliate links)

Step 1: Cut the 4x4s Smaller

It is important for the pieces to be square and for them to be all the same size. Dimensioned lumber is often not exact, or not square, so the first step is to cut the 4x4 lumber down to 3"x3". If you have a jointer, joint the piece square first.

Set the tablesaw fence to 3". Because this lumber is very thick, it is good to cut it in two passes with the blade cutting through about half of the workpiece on each pass.

Step 2: Square Up the Lumber

If you already used a jointer, you can skip this step. I don't have a jointer, so I clamped four of the pieces together and handplaned them as a group. This ensured a consistent size and a square edge.

Step 3: Paint the Lumber

Set the lumber on sawhorses and use a paint roller to paint one side of the pieces, rotate by 90°, then paint the adjacent side. Once these two sides have dried, rotate the pieces and paint the remaining two sides. I used the same color as the wall, which is a nice look, but use any color you like.

Step 4: Make a Temporary Fence for the Miter Saw

Attach a temporary fence out of scrap wood to the miter saw. Then make markings from 1" to 4" on the fence. This will act as a zero-clearance fence and prevent tearout during the repeat cuts.

Step 5: Slice All the Pieces

First cut off the end of each piece of lumber, to get a clean square end.

Use the markings on the temporary fence as a guide, and try to cut an even distribution of various lengths. For example: 1/2", 1", 1-1/2", 1-1/4", 1-3/4", 2", 2-1/2", 3", 3-1/2".

Step 6: Place the Squares

Place the cut pieces onto a piece of plywood the size you want the diffuser to be. Then arrange them in the way you want, with the end grain facing up. I tried to simulate a random arrangement for the pieces. Once you like how it looks, remove them one-by-one and number the bottoms with a marker.

Step 7: Glue the Pieces On

Using the numbering to put them in the right place, squeeze out some glue in the shape of one column of squares. This should be done one column at a time so it doesn't dry. Do not spread the glue; it will grab the end grains better if it is lumpy.

Step 8: Remove a Few of the Pieces

While the glue is still wet, remove some of the pieces so you can access the plywood. These should be some of the taller pieces, so they are easier to grab.

These empty spots will be used to screw the artwork to the wall. These pieces should be removed from columns that are 16" from each other, so it can be mounted to the wall studs.

Step 9: Nail It From the Back

If you have a finish nailer, once the glue is dry, lean the piece up onto one edge and finish nail through the back into the taller pieces. This will help to reinforce the piece.

Step 10: Screw It to the Wall

Prop up the piece where it will live on the wall, or attach a support cleat to the wall studs and rest it on that, and then attach the plywood through the empty spots using 2-1/2" cabinet screws. The cabinet screws have a washer head, which will distribute the force and hold the piece better.

Step 11: Replace the Missing Pieces

Place the removed pieces back in their spots to cover up the cabinet screws. They should fit very snugly on their own, but if they are loose, you can add a magnet on the back to stick to the screws.

Step 12: Cut a Cove Moulding (optional)

Using a cove bit in the router table and multiple passes, cut a cove moulding. Start with a piece that is much wider than necessary, and then cut off the cove part on the table saw after it has been routed. This makes it safer and easier to cut the cove on the router table.

Step 13: Cut the Miters

Measure the sides of the art piece on the wall, and cut miters in the cove moulding to fit around it. This can be done with a miter saw, miter box, or a 45° tablesaw sled.

Step 14: Attach the Moulding to the Wall

Use a finish nailer to attach the moulding to the wall around the edge of the art piece. I used a 16 gauge nailer, but 18 gauge will also work.

Step 15: Admire

It's done! Good job!

Also shown is a diffuser made in the same way, but with narrower pieces. I like the look of it, but it requires a lot more pieces when using narrower pieces.

Thanks for looking! Make sure to rate this project and follow me!

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