• If your computer uses a Microsoft Windows-based Operating System(98/2000/ME/XP/NT 4.0) with a Pentium II processor (or greater) or the Macintosh OSX operating system, download the latest free RealOne Windows Player. This program will provide the highest sound quality available for the sound samples you find on the Harpsongs website. 
• If your computer uses Microsoft Windows 95, download RealPlayer 8.
• If your computer uses Microsoft Windows 3.1, NT 3.5.x, or Unix, download RealPlayer 5.
• Unix/Linux users may wish to download the Community Supported Player.
• For the Macintosh OSX download the Mac RealOne Player.
• For older Mac systems check the RealPlayer Archives.

* Warning: Don't get caught up in one of RealPlayer's marketing loops - you can download their basis player FREE, so don't be snookered. Also, avoid clicking on any of their "download sponsors" while the player is being downloaded or you will end up with needless software on your computer riddled with marketing entanglements.

I'd rather download the Windows Media Player: