So I got the word that we're going to put in a new floor in the living-room. This means that everything there must be moved to other places, including the "data centre".
It's always a hassle to move the computer around; once in a while I do an all-out cleaning of the corner where the computer table is – disconnecting every cable, cleaning out and reconnecting – it's always a pain in the ass.
Anyway, since I have no idea of how long it will take to fix the floor, I decided to set it up somewhere else so I wouldn't be without internet/music. This new location is granddad's old room that we've used sort of as a storage room since he moved out.
It's a very makeshift solution and I probably won't get accustomed to it in a long time, but at least it's an acoustical improvement over the old corner where there was a crazy spike at around 120-150Hz. (Yes, I'm actually considering leaving it here. A bit crazy, I know, but we all go a little crazy sometimes.)
I've also found out that it wasn't just the corner responsible for the loud fan-noise; the eMac fan is obscenely noisy.
We'll see how it all works out.