You'll get so much more from the 803's.I sold the 803N and kept up on the D's though I haven't been back to chop to hear new Diamonds (I wonder if there worth price hike).Bryston is just a good solid amp that unless your in a church sized room should work well (they bench at about 50 wpc over rated 225wpc).And I know that though the 803's may have had a 8ohm 90db spec they had a nasty impedance swing that cried out for what should worked with 100 and need double that at minimum even in smaller rooms.Brsyton is good choice.The B&W's are fogiving nd warm speaker that don't "get right" with tubes etc.That said while a solid good amp they have less character than some.You might want the warmth of a Plinus.Maybe Pass would be a a choice.Ayre has gotten good ratings.And if you want great sound that won't run out of gass Parasound JC-1 400 mono's would be great.I sold Krell with them which gave great bass "grip" (though I didn't like metallic mids).McIntosh would be lush.If you had asked about used 4 B ST I would not have opened up putting research and listening into what you thought was your liking but the extra cost of SST makes me think you can swing other new or used.But Bryton is fine product and though 7 mono's would be better and if you went used (20 year warranty and bullet proof) my freind got his Maggie 3.6's "right" when I got for him a 4B ST (we didn't sell it) gave him option of adding second and vertically bi-amping or better laterally with the Bryston x-over.You'll love the D's but you might get more out of Pass character while I would like JC-1's or warmth of Plinius (I like tube amps and they have that tube sound that most SS products don't).Still you won't suffer with the combo as again B&W's if you like sound are much less finicky than some speaker with amp matching.But Bryston is yeoman man like products that do job and are built to last.The 804's will be ridiculous (I always liked 805's and 803's waaaay more) and the Arcam will sound like a Sony $200 A/V receiver in comparison
Enjoy
Chazz
Enjoy
Chazz