SBBB bluetooth speaker

It's a Small Box with Big Bass
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(at least that's what i want it to be...)
https://youtu.be/05p6EjRsf4E
Note : the microphone of the camera really doesn't do justice to the sound :-/

Features :
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- True extra bass sound system with Xtra Long Pass (© XLP) passive radiator, doesn't sound as cool as it's name but not bad either
- class D amp between 10-15w rms
- 2x 18650 battery (should get 10 hours at reasonable level)

What you have to put inside :
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- SQ 251 4ohms speaker https://fr.aliexpress.com/item/4000540507550.html
- passive radiator 40*70 https://fr.aliexpress.com/item/4001014691399.html
- pam8610 with integrated bluetooth https://fr.aliexpress.com/item/32732590506.html
- dc step up that could handle 2A or more from ~4V input to 15V output
The one in picture is pretty decent
- some capacitor to smooth current spike (I put 2200 + 3300 /25V at the amplifier voltage input and 2200 10V at the st