The future of high end audio is on disk, not disc. Audiophiles who have traditionally been allergic to anything related to a computer are going to need disk space. Right now this means spinning hard drives that will eventually fail. In the not to distant future Audiophiles will be able to replace these traditional disks with Solid State Drives. These SSDs have a maximum number of read/write cycles that is very high, but eventually wear out as well. Since SSDs are not available in the high capacity that audiophiles need this article focuses on traditional disks.

The Basics
So, you've got a few thousand CDs and you want to store them on your music server. You also download high resolution audio from numerous Internet sites like Linn Records, MusicGiants, and iTrax. You need a disk solution that is easy, within your budget, and will last for awhile. Nobody wants to fiddle with disk configuration or call The Geek Squad to upgrade their hard drives, when they could be listening to the latest Britney Spears album Blackout or Bolero from Eiji Oue and the Minnesota Orchestra, Reference Recordings (RR-92). Honestly, I have both and listen to both. I’m a fan of music and entertainment. One is music and entertainment while the other is more entertainment than music. Whether you use a canned music server like the McIntosh MS750 or a custom music server like a Mac Mini you need disk. The Mac Mini needs disk to get up and running whereas the McIntosh MS750 needs disk to backup the internal drive that comes standard with the unit. Yes, I mentioned backing up. I sense another allergic reaction from audiophiles worldwide. To be honest, you don’t have to back up anything. It all comes down to how much time and money you have to purchase music again, or to get a “ripping” service to reload your music. If you don’t mind loading a few thousand CDs and losing some irretrievable downloaded music, then don’t backup anything. I can see the out of context quote right now.

“To be honest, you don’t have to back up anything.”
Computer Audiophile, 01/2008

Size
How large of drive you should get is best answered by you. Remember to consider the format factor. A 750 GB drive will not get you 750 GB of usable space. Roughly 10% of that will be lost to formatting and you'll want to leave another 10% as free space on the drive. You can try using formulas to determine how many songs at what bit rate / sample rate you can fit on your drive. I recommend copying a fewCDs at your desired rate to get get an average size. This way there are no external variables to consider. Right now 750 GB drives are the best deal on the Internet. Wow is this article going to be dated soon :-)