> one should stick to SSDs for sound
I think you should stick to SSDs for performance reasons. :-) I can't go back to spinning drives for my desktop computers.
But here is one idea for you... Backblaze started in my dive one bedroom rental apartment in Palo Alto, California. Here is what that looks like with cubical walls setup in my living room: https://i.imgur.com/twu5vKe.jpg
Ok, so my desk in that picture is the one on the far right. I positioned my desk in the living room against a wall carefully so that my gas furnace room (with a door) was DIRECTLY on the other side of the wall. Then I put the computer inside the furnace room, drilled a hole through the drywall large enough to run the monitor cables and USB for the keyboard and mouse, and my desk was SILENT.
I caught SO MUCH grief for putting my computer in a furnace room, but the silence was worth it. I still claim to this day that if the furnace pumped out all of it's heat into the closet surrounding the furnace that would be a terrible design, that's not how it works at all. :-) But if it bothers you deeply, find a wall where there is a coat closet on the other side.
Here are more pictures of the original combination furnace room and machine room in the first Backblaze Corporate Headquarters: https://www.ski-epic.com/2007_small_business_setup/dell_xps_...