I use the LaCie 3TB d2 USB 3.0 Thunderbolt Series Hard Drive with my MAC Book Pro computer. See:
DataTale quad bay Thunderbolt drive http://oyendigital.com/hard-drives/store/RS-M4T.html
Filled with 4 Hitachi Deskstar 4TB drives.
Looking forward to high quality Thunderbolt cable to try between this storage unit and my Mac Mini.
Like you, I have an OWC case, but the drive was modified by Benjamin at Mojo Audio. He put in a 4TB AV drive, added some sound proofing and/or vibration absorption, and the drive is almost completely quiet. You have to be right on top of it, without the music on, in order to hear it.
As a photographer, I have many other drives, including the standard OWC Mercury Elite Pros, which is probably what you have. They're all too noisy for the stereo. I also have a couple of OWC Raid drives that sound like the local regional airport.
I use Seagate server grade drives in my NAS in a mirrored RAID config. They are quiet and very tough.
Started out using regular drives and they failed in a few months
RAID is very tough on drives, so server grade is important - according to my friends at the computer store.
Got the same RAID config drives on my photo processing machine and the are great.
I use a Synology 415+ NAS and keep the hard drives out of the room with my stereo. The NAS is populated with HGST drives. HGST drives have one of the lowest failure rate among high capacity hard drives. I have a Samsung solid state drive in my computer.
I am leaning more and more toward a network streamer and getting the (laptop) computer out of my music room.
I can't emphasize enough how important it is to back up your music. When I first started I ripped all my music to a Western Digital external hard drive. It died and I lost everything. I ended up re-ripping everything. I now not only have my NAS mirrored but I also have everything backed up off site.
I was using the OWC Mercury Elite Pro 4TB Dual Bay solution managed using SoftRaid set up as Raid 1+0 configuration. A couple of weeks ago the Primary drive failed. Ouch! Fortunately the Raid array saved my data on the secondary drive.
Purchased the OWC Mercury Elite Pro Qx2 (12TB). The Raid array is hardware based now which alleviates needing Raid software. Set it up in Raid 10 configuration. Could not be happier with its performance. It is quieter than the previous drives....need to place my ear next to enclosure to hear anything and just a whisper...not audible from my listening position.
Perfect solution for my system.