It is not the quietest product. On the other hand noise level is ok to keep it in the room next to mine. It may not fit if you wish to work with it on the desk.
I'm new to the world of NAS so no technical insight, but with two Synology 12tb drives it's surprisingly quiet - a few muted chirups when loading it up with my dvd and cd collection and after that it just sits quietly in the corner.