DIY: Portable Mp3/Mp4 Bluetooth Speaker

Homemade boombox, radio, sd/usb mp3/mp4 player
Mp4 module:
Amp module:
Passive radiators:
18650 Batteries:
18650 holder:
4S meter:
DC module:
DC/DC isolator:
Mini switch:
Power jack:

Drill Bit used :
Multi charger:

-Using dc/dc isolator B1212S to avoid ground loop/ "hum" effect.
-Width 30cm, height 9.5cm, depth 12cm.
-Pcb with cell balance function.
-Schematic at 13:15

Copyright free music list:
Kozah - Haha [NCS Release]
Raven & Kreyn - Bubble [NCS Release]
Jim Yosef - Moonlight [NCS Release]
Ascence - Rules [NCS Release]
Moving On (Instrumental) MBB & Jonas Schmidt [Vlog]
Elektronomia - Heaven [NCS Release]
Max Brhon - Humanity [NCS Release]
Raiko - Lightning Child

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