Great to meet you!
Nice to see some Belgians 
When it comes to quiting down my asic miners, I did a few small thing to get the noise down to almost impreceptable levels. So it’s all about air flow!
- I removed the metal grids from the cooling fans.
- I removed the back plates from my miners and any grids that can restrict the flow of air through the cooling ribs of the hashing boards.
- I took long air ducts that have internal rockwool insulation ( 30cm in diameter and 1.5m in length ) and put the miner inside ( with the side that blows out hot air.
- From the shipping box that the machine came in, I made an inlet sound damper ( by covering the box with carpet on the inside ).
Result: the machines are humming very quietly! The air flows without obstructions and by doing so, the fans don’t have to rotate too fast. So overall sound is reduced to extremely low levels.
One thing to mention, is that you must be prepared to pay for the power yourself for at least 2 to 3 years!!! Mining is a looooong term game. You have to be very patient!
)