Thank you for your comments.
Good point to consider the C-3850. I have never compared alle the preamps. And I have time, I can wait until there is a good offer in my region.
I use a Shunyata Alpha v2 for main power to the Isotek Sigmas and the rest are Kharma power cables I got very cheap and which are very good though. For signal I use a Refine Audio Ultima Musica XLR. Refine make the best signal cables I have ever tested in my region. For ethernet streaming I use Ansuz cables, also the best I have ever tested.
Does anyone have compared class A versus class A/B poweramps? Is it the same, as with the integrated, that A/B is a bit more detailed, but edgy and cooler and class A are smoother, warmer and rounder?
About the speakers: I know of course that the D series of B&W have diamond tweeters. :)
The 803D3 can sound harsh with the wrong electronic such as Rotel or Classé or T&A etc. I heard them with a Michi Rotel X5 which was very thin sounding and harsh, compared to the E-480. On a hifi exhibition i heard the 801D4 with Classé Delta amps. It almost hurt my ears, so harsh was the treble. But I also know, how beautiful the B&W can sound, when they fit with the electronic. And as I wrote, with the class A Accuphases (E-800, 2850/A75) it was far away from forward. It’s always the combo speaker <> electronic that makes the sound. The 803D3 are difficult to drive, when you buy just anything. But with the right match, they are wonderful.