Introduction: How to Build a Powerful Bluetooth Speaker

I have always wanted a low budget boombox with powerful bass but it was always very. So I thought wouldn't it be nice to bulid a portable boombox with powerful bass, clear vocals & at a low cost


To build a powerful Bluetooth speaker you need
Two 4"subwoofer
Two 1" tweeter with 1uf capacitor
Two passive radiators
A TPA3116d2 amplifier: 2x100w
A Bluetooth receiver module
Epoxy glue
A DC-DC converter
19v,4A adaptor
A piece of 35"x 15" board

Step 1: Dimensioning & Cutting for the Speaker Enclosure

First you how to decide what type of box you want weather sealed or ported.
Ported are usually too big so am doing sealed complimented me passive radiators.
The dimension for this is 14"x7.5"x7.5"
Now we cut four rectangle of 14"x7.5" & two squares of 7.5"x7.5"
Then cut a circle of diameter 4" in the two squares, this is for the two drivers while one would be firing down the would be firing up thereby giving a surround sound.
Also we have to cut two holes of diameter 1" for the tweeters on two the rectangles to also give a surround sound, the for the passive radiators I used 1rectangular & a circular passive radiator so therefore cut hole for them according to their sizes.

Step 2: Putting the Box Together

Putting the box together i took two rectangular boards first & measured 1" from the bottom on both boards considering the down firing speakers then glued the square cut parts to it using the epoxy glue. Now to create a compartment inside the speaker box to hold the amplifier & Bluetooth module, I made a container of 7"x3"x2.5" fit in the middle of the two side cuboid using a wooden board put the passive radiators in place making sure there is no air leak then cut the board for the front into three parts with the side of the small container in the middle,having done that we have to put the whole box together sealing it completely but the container inside would be open to the front where the amplifier & Bluetooth module can be maintained & fitted through.

Step 3: Fittings

Now with your box completed two pairs of wires runs from the empty speaker box to the amplifier container. Then fit the Bluetooth module on the front board cut to the size of the container, now connect the tweeters in parallel to the speakers then we secure the amplifier in the container using screws. The DC to DC converter is also mount using screws or glue.Now the speakers & tweeters are connected to the two wires from the amp container & secured in their respective bored/cut holes using screws or glue. Now fix the switch & pin Port on the area of the box that exits into the amp container.

Step 4: Finishing

Now we have to do is connect all the wires. First connect a sir from the positive terminal of the pin Port to the switch & from the output of the switch to the Vc of the amp & the positive input terminal of the DC to dc converter, now make a connection from the negative pin port to the negative input of the 'DC to dc converter' & the ground 'G' of the amp. Then connect the two pairs of wires leading to the speakers to ch1 & ch2 respectively minding the positives and negatives,after this is done we connect the Bluetooth module to the output of the DC to DC converter minding the polarity & the signal input of the amp to the signal output of the Bluetooth module.
With all the connections completed & security with tape,we close the amplifier container & secure it with screws
You can now plug your 19v adapter, switch on & enjoy good sounds at a lower cost.
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