Introduction: Easy Bluetooth Subwoofer Speaker (80W)

About: Industrial Engineer

Hi everyone!

Again I found some old speakers which we didn't use so I thought lets make something nice of them :)

I designed a wooden box to put them in and this time I was looking for some nice wood.

The speakers I used are:

- Subwoofer 40W speaker

- Left and right speaker also about 35W

I bought an amplifier on ebay for 10$ and it works actually very good!

I use this speaker on my room and it has bluetooth so very handy to play music.

Step 1: Collect the Parts You Need

What do you need?

- Amplifier:Ebay

This subwoofer amplifier has a 40W subwoofer output and 20W left and right output.

If you got some higher power speakers you can use another subwoofer amplifier like this from Ebay

I should not recommend the amplifier I used because it was diy kit so I needed to solder every component separately.

- Bluetooth usb:Ebay

Still the best option for easy bluetooth installation and has a good bluetooth range.

The aux input can also be used so you have a double use of the bluetooth usb.

- 12V to 5V converter:Ebay

This module is used to convert the 12V from the power supply to 5V to power the bluetooth usb.

- 12V DC adapter:Ebay

You will need 2 of these to power the amp and the '12-5V converter' for the bluetooth usb.

- Speaker

I had some speakers laying around from my dad's old car, so I tought let's make something useful with them!

- Switches: Ebay

I used toggle switches, one to power on the speaker amp and another to power on the bluetooth module.

- Wood

My father brought me some wood in 2 colors so I could combine the grey and black to give it a nice look.

- Wires


Step 2: Put Electric Parts Together

Bluetooth usb

First you need to open the bluetooth usb and solder wires to the tabs I marked with L, R and GND.

Now you need to connect these 3 wires to the aux input of the amplifier to transfer the audio from the bluetooth usb to the amplifier.

Plug your usb into the 12V to 5V converter, and power the converter with 1 of your 12V power supplies.

Power supply

You only need to plus 1 socket into the wall, so open the power supplies and connect both input voltages together. Use the one plug and put the plug into the wood case so you can put you power cable into it.


I putted 2 switches into the speaker.

The first one will cut the main power (230V) so no current can flow through the power supplies when powered of.

The second switch is placed between the 12V PS and the 12V-5V converter.


Connect the speakers to the inputs marked in the pictures.

Step 3: Make the Enclosure of the Speaker

Drilling holes

I made holes for the speakers, switches, volume knob, power on LED, AUX input.

Glue and screws

In the next step I glued all parts on the wood and after these were dry I could glue the hole speaker together.

I screwed the back panel so I could always open it. I also made a hole in this backpanel to glue a pvc pipe.

This is used so the air can escape while the subwoofer is doing his job.

Here are some pictures during the assemblage, but I forgot to make a lot of pictures so if you have any questions ask me ;)

Step 4: Giving the Final Touch to the Speaker

If you have any questions, feel free to ask anything!

After I made this I thought it would be nice to make batteries inside, so they would be charging the whole time, but when you want to take the speaker outside, it will be powered due the batteries.

Maybe an idea for some ;)

Box Contest 2017

Runner Up in the
Box Contest 2017