If you set it up to spin down the disk(s), you won't hear it. If you don't allow for disk spindown, it'll be annoying.
Since you don't intend to use any of its advanced functionality, I recommend that you go for something cheaper than DS224+. Like DS223 or DS223j
When I had a rack at home, it was a silent one (so almost completely sealed). I had a fat duct coming in from the outside into the bottom of the rack and another fat duct taking the hot air from the top outside. But in winter, I made sure it was blowing that hot air into the living space.
Don't leave us hanging! They're quite what?
When I started my first serious networking job, there was a syslog server in our datacentre that had been running nonstop for almost a decade. It was an ancient radiator-white supemicro 3u server with 6 SCSI disks. I decommissioned that server 7 years later. Those SCSI disks had been running nonstop for 16+ years without a single problem. The inside of the server was covered in black plastic dust from the slowly disintegrating case fans. Other than half the case fans not working, there was nothing wrong with that server.
Encrypted disk in my desk drawer at work. Contains everything apart from my movie collection. Many of my colleagues have now copied my approach.
Because of jellyfin? Mine is restricted to 3GB and runs happily on raspberry pi 4. I've even had it run on 2GB pi4 and it only struggled occasionally.
DM is death match. HM is a clothing brand (Hennes & Mauritz)