anyone had a listen to the b w 803d's

Duc999, that's probably why they sounded "flat". Marantz or any other "receiver" is not going to do the 800s justice, particularly the D models. At the very least, try them with Rotel, but match them with Classe to really hear the potential of the speakers.

Why in anyone's right mind would you pair a $9K speaker with a receiver? You simply cannot make a credible determination regarding the performance of any audio component unless the supporting components are suitable.

clarify, the marantz were power blocks biamped.

I am useing,classe pre,krell cd,jefrowland 150w amp-M112.

They sound nice but I could name ten or so other speakers at their price points that, to me at least, sound better. The brands named above (although I've not heard the Piega). Would add Sonus F and Montana.
I think the 800 series is still made in the Uk. Other than the ten thousand dollar two way and the one that looks like a snail, B and W makes their products in China. Q

I have found Marantz to sound pretty good and be very under rated. It is hard to say because B&Ws are one of the few brands that REALLY need lots of power... You can get lots of power cheap from Rotel (very cheap used). I heard The 803D back to back on Classe' amps and rotel amps. The Classe's were a bit better but if you did not hear them back to back you may not know what you were missing.

So what would you be missing with Rotel? IMO a bit of treble refinement and a touch of bass control at higher volumes.

Also most people seem to think the Sophias are pretty easy to drive but still diverse good equipment.