JRiver Media Center is extremely flexible all-around media player. Great application for both audio and home theatre enthusiast with range of quality, patented built-in plugins. And also very good customer support as bonus. Guess you get what you paid for. I recommend this software if you have extra moolah to burn (hardware is still the priority).

However I don't hear and don't believe there's audible sound quality difference between any music / media player. Jplay made such bold claim on their part but so far they haven't come with any substantial when asked to (on Hydrogenaudio).