

My main headphones. Sony WI-C200.
Still works. Battery replaced with the 2017-2018 chinese 18650 and the speakers are changed.
~1mo of battery life, and 5h of charging.(tested)
And yeah, they're sounds really good.
Is it horrible? Yeah. Weird? Absolutely. Works fine? Of course!
I was using a $2 chinese soldering iron, self-made rosin, and some weird tin that I got from the PSU PCB.
I got them from my father, and they was completely dead. So, I used some trash, aand that's it.
And about my desk, that was just my printer cartridge refilling.