Hughes123:The Roksan would be a perfect partner for the 685s - plenty of power and a nicely matched tonality. I have heard the RA-04 with the 685s, and it didn't really impress that much - however, that was a long time ago - I felt the treble was a bit artificial and there was a lack of drive to the sound so it didn't interest me at all. They do need the best part of 100watts per channel into 8ohms to get the best from them.
Also, if anyone says that your CD player isn't up to the job for such expensive components, ignore them - IT IS! Just because it's fairly cheap, doesn't mean it's not good value!
I wouldnt say that the Marantz is cheap; far from it BUT the soundstage of Marantz gear, IMO, doesnt suit B&W speakers at all.
As ive said before, with the right speakers (M/A, Mordaunt Short, Dali etc...) the Marantz gear is good but with B&W, its thin and a bit forward, clinical sometimes.
B&W need a good amount of 'well' to really make them sing so separates like Cyrus, Arcam and Roksan really do well with them. NAD is another good make that gel very well with B&W speakers.