My grandpa recently passed away and my family and I went through his house taking what we want for his remembrance. I found an old wooden 5- or 10-liters wine barrel. When I saw this small barrel, it was clear for me to turn it into a Bluetooth speaker.

With the years the wood became greasy and the rings were rusty.

At this point I want to make clear, that this is no instructable on how to build a Bluetooth speaker from scratch with all the electronics components. I took preassembled components and only show you how to wire them up.

Material:

Small barrel
Bluetooth amplifier board (ARCELI TPA3116 2x50W Wireless Bluetooth 4.0 Audio Receiver Board/DIY Stereo Amplifier Module DC 8-26V Remote Control, https://www.amazon.com/ARCELI-Wireless-Bluetooth-...
2 speakers (Visaton frs8, https://www.amazon.com/Visaton-FRS8-8-3-3-Full-Ra...
DC female plug (5.5x2.5mm)
Black spray paint, matt
Old laptop charger cable (make sure you buy the correct DC female plug for it)
Heat shrink tube
Some screws, depending on your construction
Linseed oil
vinegar concentrate (now it sounds like a salad…)

Tools:

Cordless drill/driver (really helps, if it’s charged), drills and screwdriver bits
Hole saw
Router or rasp
Random orbit sander
Detail sander
Compass, ruler
Wire stripper
Crimping tool
Hot air gun
Multimeter

Step 1: Remove the Rings

Remove the rings. Take out the nails if there are any.

Step 2: Cut the Opening for the Speakers

Find the center of the barrels top and bottom. I measured the diameter first, then used a compass to approximately find the center. I did that by trial and error – I set the compass to the radius as measured before and put it into the approximate center. Then I moved the compass until it was nearly in the middle. This doesn’t have to be 100 percent perfectly measured. You will never see both sides at the same time.

Take a hole saw and open the top and bottom for the speakers. If your hole saw is not big enough, draw a line to which the material has to be removed and remove it either with a rasp or with a handheld router like I did.

Step 3: Sanding

Give it an overall sanding. Don’t forget the base. Take the speakers and mark where to drill the holes to screw on the speakers later. Make sure the speakers are orientated in the same way so that they are not shifted by 45° or so. Drill the holes.

Step 4: Finish the Barrel

Take linseed oil to finish the barrel. Wipe on a few coats of linseed oil and remove the excessive oil in between.

Step 5: Electronical Installation

Take some scrap wires. They have to be at least some centimeters longer that the barrel itself – for installation purposes.

Strip the insulation of the wires at the ends and crimp terminal lugs and wire end ferrules on it. Cover it with heat shrink tube or with electrical tape.

Make sure you connect the positive terminals of the speakers and the Bluetooth amplifier board with each other, as well as the negative terminals.

This instruction should guide you towards connecting the board, but I’m not taking any responsibility. If you’re not one hundred percent sure what you’re doing, ask an electrician to help you connecting the power wires.

There is a symbol on (I think) each power supply, stating the polarity of the plug – see the picture. In my case the inner part is positive, the outer part is negative. Now you have to find out the polarity of the female plug. Don’t necessarily trust the polarity given on the plug. Check the continuity with a multimeter. Connect one multimeter probe with one of the screw terminals in the back of the plug. Connect the other to the inner pin or the outer tube and check the resistance. If the resistance is low, you found the interconnection of the power connector. Now memorize (or better mark) which terminal is positive and negative and connect the respective wires to it.

Screw on the power wires from the DC female plug to the power terminal on the Bluetooth amplifier board. Use hot glue to fix the DC plug in place. I used the hole that was in one of the sides of the barrel for the barrel spigot. It had the perfect size for the connector.

Take an aluminum plate and drill 4 holes to attach the Bluetooth amplifier board. Use screws as spacers between the conductive aluminum and the power terminals on the PCB. I used the aluminum plate as a spacer, that the amplifier board doesn’t directly touch the wood.

Mount the first speaker to one side of the barrel. For this I used some screws where I painted the heads black for aesthetic purposes as I hadn’t had black screws.

Cut two pieces of foam for acoustic insulation to avoid echo in the barrel. Punch a hole in the middle and feed the speaker wires through before finally connecting them to the amplifier board.

Stick in the amplifier board into the barrel from the side where no speaker is mounted yet. Now insert the second piece of foam and mount the second speaker. Don’t forget to wire it to the amplifier board before mounting the speaker.

Step 6: Making the Rings

Remove the rust from the rings you removed in the first step. I used vinegar concentrate and a tooth brush for that. After you removed all the rust, remove any of the loose paint. Now spray paint the rings with black spray lacquer.

Let them dry and put back the rings to the barrel. Use a few (black headed) nails to secure them in place.

Step 7: Plug in and Enjoy...

Plug in the laptop cable, connect the Bluetooth with your cell phone and enjoy the music.

In conclusion I must say, that it's not a high end soundbox. But it does it's job. If you're a music enthusiast you should definitely go for high end speakers and high end amplifiers.

But since I built it, I used it everyday. For me the sound is good enough and it always reminds me of my grandpa.