The HD-AE5000 hard drive is a unique design which includes some additional audio features for the keyboard. Although the hard drive itself is a standard item, the circuit board and connections to the keyboard electronics are unique. The software is intermingled with the keyboard software after installation. It is very easy to install (takes about 10 to 15 minutes). I paid $750 in the U.S plus another $80 for the Tech Manager Software. A really steep price but once you have the hard drive you wouldn't want to live without it. For sources of supply contact Key Soft Service at the following address. http://www.keysoftservice.ch/