Recycled Portable Bluetooth Speakers

Intro: Recycled Portable Bluetooth Speakers

Hi All,

I feel good about recycling and in this project, I recycled 3 items

• Speakers : extracted from old desktop speaker
• Lithium ion battery from old laptop
• Wood from left over / discarded stack

Features

• Bluetooth / AUX in/ FM/ TF card
• Ultra thin ( just 50mm)
• Volume control
• Remote control
• 6 to 9 hr battery backup
• Weight Less than 500 gms
• Recycles speakers total output : 6 W

STEP 1: What Do We Need

Material

• 2 Speakers ( 3 W each)
• PAM8403 Amplifier with volume control ( 3w+3W)
• MP3 / Bluetooth kit
• 2 Li Ion Battery (18650)
• TP4056 with Battery protection
• 2 DC step up boost - MT3608
• Wires
• PlyWood
• Switch - push button
• Screws ( I extracted these from the original speakers
  • 8 screws to hold speakers
  • 8 screws to hold the back plate

Tools

• Hammer
• Fevicol / PVA glue
• Black Spray paint
• Soldering iron / wire
• Hot gluegun
• JigSaw with wood blade
• Paper tape
• Sand Paper ( 80, 150 and 220 Grit )

STEP 2: Frame

To hold all the assembly, we will use 10mm plywood.

• Cut a 2 pieces each of
  • 45mm X 180mm
  • 45mm X 100mm
• Fix them at the edges at 90° as shown
• Use fevicol or PVA glue
• Use paper tape to hold all pieces in place
• Let it dry for 4 hours
• Using 80 grit sandpaper, make the edges smooth and straight

STEP 3: Front Side

• Cut a 180mm x 110mm plywood or MDF ( 4 mm thickness)
• Make 45mm diameter holes for speakers, Note that my speakers were 50mm diameter
• Cut appropriate holes for
  • Bluetooth / MP3 plate
  • Volume control ( PAM 8403)
  • Switch ( Not show in images, as I forgot and I added it while working on the electronic stuff )
• Spray paint black ( glossy) as shown

STEP 4: Back Side

• Cut a 180mm x 110mm plywood or MDF ( 4 mm thickness)
• Drill two hole for 16mm dia meter tube for bass as shown
• Add required holes for TP4056 ( micro usb in)
• and LED indicator ( I use a piece of stirrer for led indicator)

STEP 5: Inside

• Now to fix the speakers, we need to cut a mdf sheet (4mm thick) as shown
• For battery fix two holder as show, we will hot glue battery on these, later
• Let it fry for 4 hours

STEP 6: Electronic

• Follow the logical circuit diagram ( each single line represents both positive and negative wires)
• TP4056 is connected to battery and two MT 3608
• MT3608 is set at 5 V for PAM8403 and 9 V for Bluetooth Kit
• Output from Bluetooth kit is connected to input of PAM8403
• Two speakers are connected to PAM8403
• Test the circuit before Assembly

STEP 7: Putting All Together

Putting all together is difficult and take time, I fixed thing in following order

• Power switch
• PAM8403
• Speakers
• TP4056 and MT3608
• Battery
• Bluetooth kit

Pre-solder long wires to PAM8403, bluetooth kit and TP4056

Hot glue things in place

STEP 8: Enjoy

After all the wiring is done, close the back panel. I used 8 screws to ensure no sound leakage.

Test it using different inputs like FM, USB etc

Improvement for furture

• My speakers were 2w and output 3w, so disturbance at high volume
• Current limited by TP4056 at high volumes, due to high current pulled by amplifier

Please share your comments, if you liked it

Comments

[VickyF21]

Excuse me,
What is this?

[Amit_Jain]

Hi, this is 3.7 v to 5 v step-up convertor with usb port

[VickyF21]

Why doesn't the tutorial above use the item?

[Amit_Jain]

I wanted to use it, but the battery and usb step-up convertor could not provide enough current for the amplifier. So i had to replace the battery with two 18650 and better stepup convertor

[VickyF21]

Ok, thank you
One last question, where is the power switch placed?

[Amit_Jain]

It is a push button, placed on the left top corner. See the first picture on this article

[VickyF21]

I know that, what I mean is where to connect the push button

[Amit_Jain]

Hi, it conected betwen output of tp4056 and step up convertors

[VickyF21]

I have practiced it but it can't sound, what is the cause?

[Amit_Jain]

Please share photis of your connections and a video

Upload on YouTube and send me please

[VickyF21]

This is the link https://youtu.be/3C6izHx16J4

[Amit_Jain]

Question
Is the music module restarting repeatedly?

Looks like ground pin is not connected somewhere.
Reduce volume on amplifier and then switch on, donot keep on max

Also try running whole setup on a 5 v charger

[VickyF21]

Question
Is the music module restarting repeatedly?
* No, the bluetooth kit runs normally

Looks like ground pin is not connected somewhere.
Reduce volume on amplifier and then switch on, donot keep on max
*The ground is already connected & for the volume I have tried but still can't

Also try running whole setup on a 5 v charger
*Still can't, I've tried

Is there another solution?

[Amit_Jain]

It has to be wrong or loose connections, not muxh to troubleshoot....

If not the wires, i donot know.. sorry

[VickyF21]

Yes it's okay

[vickyferiansyah]

I want to ask
How to set the volt at PAM8403 ?

[Amit_Jain]

Pam8403 is amplifier, it needs 5v

[Surajit Majumdar]

Awesome speaker bro :)

[Amit_Jain]

thanks

[sleepy120]

Dont need 9v for bluetooth. Just bypass the 5V regulator lm7805 on the board and power directly with 5V (short left and right pin with solder).

As a side note, are there any bluetooth modules that default to bluetooth when turning on?