Managed to combine the driver from an Anker Soundcore Mini & electronicals from an 808 Canz 2. It's not loud because it has no passive radiator. It's surprisingly sealed despite not being air tight or having any gaskets. The benefit to not having a passive radiator is it being much lighter. If the enclosure is cracked open, it sounds awful.

A key requirement was getting it to turn on without the button. Hooking some 5V points directly to USB got it to turn on with power. To get it to pair, you have to disconnect the brown wire. Transistor power but not capacitor power causes it to pair. Of course, this also requires ungluing it. There could be an exposed jumper.

It got a teardrop shape to more efficiently use the corner space. It has the largest possible cavity for its size. The string holes should be farther from the corner.

There is potential in 3D printed speakers. It could possibly benefit from a transmission line but it would be heavier. Obtaining the air tight seal for a passive radiator is unlikely.

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Sadly, while the metronome was audible, music on this was hopeless so it was retired. The lion kingdom ordered another Soundcore mini on 2 week prime. When its passive radiator breaks, the 2 drivers will be made into a stereo pair.