Difference between B&W 800N/SIG and B&W800D

I have owned the 800 Sigs and currently own the 800d's. The 800d is a much more amazing speaker than the sigs. It could also be that the new design works better with my "cursed by the gods" room that I have, but they work for me. I am comparing these speakers using all the same equipment. I don't know if Sphere has done the same type comparison. If he listened to two different speakers in two different systems or anything else was changed when the speakers changed, could make all the difference in the world. If it were same for same, Sphere just has different tastes than I do, and/or a better room.

Could you discribe the differences between them?

I have owned the Signature 800s and now currently have the 800D. The Sig 800 were driven with Bryston 4bsst and an audio research LS-16 tube pre-amp, and the 800D is on Classe Cam-400 monos and a Classe CP-700 so it is not a direct comparison. However, I am very impressed with the diamond tweeters lack of "ringing" in the top end. Some may call it boring, but I listen to a lot of vocals and I am still often blown away with how good the 800D is. I have directly compared the 802 to the 802D and in my opinion the 802D is a much better speaker. Up and down the whole range it is much more refined, and transperent without being harsh. The bottom end on the 800D is also incredible. The only slight negetive and it may just be my small room, but sometimes they can sound a little heavy in the lower mid-bass. They are by far the best speakers I have owned and I have had many.