Introduction: Small Speaker Horn

About: William Davison Jr lives in the Tucson, Arizona area and works in the satellite defense industry. He keep busy with his many hobbies (old BMW car restorations, LEGO Robotics and Halloween effects/costumes). He…

I have always been creating speakers and looking at other speakers for inspiration. One speaker that caught my eye was the 'Little Horn Speaker' by Specimen Audio but at over $4000 USD for a pair, they were a bit out of my reach. But with the extra day off for the holiday weekend I decided that this was going to be my project... I would try my hand at making a pair similar to the Horn Speakers.

Starting off with my basic particle board speaker box (8 inch by 8 inch by 7 inch), a 3D printed mold for the horn, a cardboard tube, Plaster cloth, some glue and cotton balls, a pair of 5 inch 4 Ohm full range speakers and a pair of Boston acoustic 2 inch full range speakers also 4 Ohm.

I listen to a very large variety of music but I have heard the throaty natural sound of horns before and I hoped that they might do the same thing to some horns in a jazzy song.... so... prepare for a great little horn speaker Instructable... AND I can't wait for you to listen to how they sound!


3D printed horn mold half (Left and Right)

Plaster cloth

Bowl of water

Wood Glue

Cotton balls

1/4 Inch sheet of wood

Band Saw

Jig saw

Wood saw

Cardboard tube approximately 3 1/2 inch tube (pair, both 4 inches long)

Drill with drill bits

Speaker box, Pair

5 inch full range speaker, Pair

2 inch full range speaker, Pair

Wood clamps

Small screws with washers

Speaker wire

Step 1: Building the Horn

I had used my 3D printer to create a simple horn mold half.

STL files top, mid, and bottom are attached.

The size of the horn was such that I had to break the horns into three segments. Gluing those segments together, I was able to create a horn half, a left and right side.

Place these half horns onto some plastic wrap because the next step is going to get water on the work surface.

Cut the plaster cloth and each strip should be placed into the bowl of water. Now place each strip onto the plastic mold. cover the entire horn leaving the ends open. Layer over each strip and build up a thick half side of the horn. Do the same for each side. Allow these to dry completely. Once dry carefully peel the half off, place the two halves together and use more plaster cloth to join the two together and seal the seems. Take your time and work carefully to ensure there is no openings along the seem. Set aside and let dry.

Step 2: The Simple Speaker Box

This was a simple 8 inch by 8 inch by 7 inch particle board speaker box. I used two banana jacks for the speaker wire connection. I cut the hole to fit the 5 inch speaker. I cut another hole in the top of the speaker to route the wire to the smaller horn driver. On the bottom of each speaker box I added wood pegss for feet.

Step 3: Cut the Speaker Tube and Wood

The tube has to be long enough to allow a speaker to be inserted, leaving a space between the cone of the speaker and the top of the tube which will have another piece of wood cut to hold the horn.

I cut my cardboard tube at about 4 inches and used a wood saw and a file to clean the cardboard tube after cutting. I used the tubes to trace the top and the speaker mount insert.

File and sand the wood to clean up the edges.

I used a drill and a jig saw to cut the opening for the small speaker. I drilled pilot holes for the small screws. Four screws and washers hold the speaker.

Step 4: Assemble Speaker Tube and Add Speaker Wire

Using wood glue I assembled each tube with the small speakers. Be sure to solder the speaker wires BEFORE assembly.

Make the wires long enough that they will reach the speaker in the wooden box.

Glue the top, after gluing in the small speaker insert. I used a few clamps to hold the top until it dried.

Step 5: Final Assembly

Putting it all together, I took the speaker tube and glued it on top of the wooden speaker box. routing the wire down through the top hole and running the speakers in series, for a total speaker impedance of 8 OHMS.

For mounting the horn I used cotton balls and saturated them with wood glue forming a seal around the bottom of the horn and the top of the tube assembly.

Set aside and let dry completely.

Step 6: Sound Check and Recorded Sound

I set up the speakers on a open wall at about 4 and a half feet apart. Playing from a CD player into my Bose 550 receiver with the EQ off, I recorded some music with some nice horns in the music. The audio of the video is not great so I used a Zoom H1 Handy Recorder for better audio reproduction.

The video does has some good sound, but the WAV file sounds way better!. the sound check was very nice, great horns and full of great sound.

I do not own the rights to this music, and was using the music to demonstrate the small horn speaker.

Step 7: Future Designs

I planning on painting the speaker box and tube... I will place these in my guest room since they sound great and are a small foot print.

My next build of the small horn speaker I will make the horn larger, and add more layers to the build with the porcelain cloth. I will not use a small speaker in the throat at the bottom of the horn and will spend some money on a nice pair of main drivers. Thus trying to reducing the distance of the horn to the top of the wooden box.

Over all I am very impressed with the sound quality of the horn and the cost of the entire project staying under $50 USD was also a big plus!

Audio Challenge 2020

Participated in the
Audio Challenge 2020