Hi All,

This build is based on my friend's request. He wanted stereo speakers that could play songs from pen drive, aux in, Bluetooth etc. With decent sound for shall room... no battery backup... small form factor

In this instructables I will share how to build one

please share your comments if you like it

Step 1: What Do We Need ?

Material
- Portable stereo speakers 5w +5w
- Mp3/TF card/ Bluetooth/ FM kit
- Soft Wires
- Wooden sticks
- 2mm plywood

Tools
- Soldering iron
- Dremel
- Acrylic Paint

Make sure that audio kit has Bluetooth

Step 2: Understand What You Have

I choose a speaker which had built-in amplifier... So we need to modify power supply and input audio from our audio kit

The amplifier was PAM8403 with volume control, which can provide 3w dual channel output....

And that both worked on 5v ....

Note: if the voltages donot match, it is adviced to use a buck converter instead of voltage regulator like 7805 etc

Step 3: Break Open

Since the speakers were super glued, I had to break open it. One should do it carefully and donot damage speakers or wires...

Cut a slot based on your audio kit, mine was 8cm x 2cm.

Fix screws as needed.

Step 4: Electronics

Power Supply
- Solder wires for AC power in
- Solder wires for 5 V DC out

Amplifier
- Solder copper wires to Left and Right speakers
- Solder audio in from audio kit to amplifier
- connect to 5 V power supply

Audio Kit
- connect to power supply
- connect to audio kit to amplifier in
- Antenna for FM

FM antenna
- one can buy a telescopic antenna or just connect soft wire about 96cm long to the antenna connection

Tips :
Use copper wires for better and efficient sound.
Keep wires short.
Hot glue loose wires..

Step 5: Enclosure

Since I broke open the rear panel, I need to replace it and I should be able to reopen it for tweaks or repairs.

Attach/ fix two 3/4" wooden strips as shown, using pva glue or fevicol. Leave it to dry overnight.

Meanwhile cut a plywood of suitable length, make holes for hollow tubes and power cable. Paint it with acrylic paint to match the original color of the enclosure.

Step 6: Improvements

One could add Lithium ion batteries into it to provide some backup as well enable it to be portable.

One could replace amplifier Pam8403 with 8410 which is 10w output