That Lenovo M73 I put together a while back actually has an internal speaker — a little 2-pin thing, supposedly 1W or thereabouts. Which means it sounds like a mosquito whining, crackles on top of it, and can’t even do the one job it exists for: pinging me about a new Discord message. So the obvious fix is to just replace the damn thing. You can find M73 speakers on Taobao, and I tried one — genuine or not, the sound is equally pitiful. So go bigger: I found an 8-ohm 2W speaker for about 5 yuan. Cheap, and it shows up decently chunky.