Sorry if already mentioned and I missed, but, if you can find used anywhere available to you, an Ayre AX-5 or AX-5e (not the newer 20 series) The original AX-5, to my ears, for ultra detailed diamond speakers like the B&W Ds and the Raidho diamond speakers, is a perfect match - with a beautiful balance of musicality and a most natural presentation of detail and dynamics.
To me, some of the newer models, ie the Ayre 20 series and others, are overly dark and detailed, to the point of sounding a bit cynical, If you can find, the original Ayre integrated, AX-5 or a Bryston 4B, sst-2 (power amp model before the cubed) with a tubed pre. would be a very nice match for your B&Ws.
Best of luck.......Jim