I think Synology NAS will also work as Windows Media Server.

However, since you would be perfectly able to easily manage a full feature server, and considering inexpensive, cheap, silent hardware is available (Shuttle, or the HP N40L mentioned above, which I had never seen), I'd go that venue. You may install any OS of your choice. Linux, Windows Server, or even a plain Windows 8 pro, will be great in managing drives, RAID, Storage spaces, and you'll be able to install whatever server software you like.

As clients, Logitech ones are probably still available if you're planning to purchase now. They will surely last years, and as far as I know they are still the best option available.

Edit: I actually can't find music players on Logitech websites (I checked US and IT ones).