New rigg. B&W N804

Im rather new at this and English is not my first language, so I might be a little bit lost, sorry. Anyhow!
Just picked up a pair of N804 for cheap. So I'll be trying to assemble a nice little rigg for my cabin. 
So the question is if anyone has some experience with this speaker and what amplifiers might be compatible. I live in Sweden so the used market looks quite a bit diffrent from the states, I'd imagine.
Also, I'd really like to be able to stream music, using spotify & Tidal. What device would suit this mission?

There is a Classé CA-400 for sale aswell in the area about 1500 USD might this be a suitable power-amp?
I ran those with a Classe CA200 long ago and it was a pretty good match.  The 804s are a little bit bright and the Classe is a little bit rolled off in the highs.  A 400 is a lot more power than you need but it'd certainly work.  If I were you, for $1,500 I'd be looking for something newer with less power.  
I've Bern looking at Hegels integrated H300. 250wpch with built in dac, about the same money. Might be better? 
It's got enough power.  I couldn't guess whether it'd sound better but a CA400 is old and I'd be worried about reliability.  I didn't find the 804s particularly power hungry when I had them.  I found placement to be somewhat tricky.  Having both woofers and the port firing out the front means they can really excite room nodes and give lumpy bass response in bad rooms.  
Hegel is a very nice integrated!  The H300 is the older generation and has a more smoother and laid back sound (for Hegel).  The second gen (i.e. H160 / H360) revised the preamp section and were higher resolution and more forward with more attack and detail.
For streaming, many find Bluesound Node2 a very good option. It has a decent built in DAC or can be connected to better (external) DACs for better sound. Under $500 USD. 
Greetings From NJ
 Have been to Ostersund Sweeden wonderful place on earth
 I am familiar with NT 804 would hunt down a Primare 30 or 31 integrated.
I used to compete with a local Classe dealer and Primare would easily get the nod. Try and run it with a balanced matching Primare CD player and you should find its the Bees Knees.
 Best JohnnyR
You can use the Node2 as a preamp but all the “controls”, e.g., volume, etc., will need to be made via its BlueOS app on phone or tablet. While the sound initially seemed dynamic and crisp, I personally thought it sounded a bit dry and lifeless after a few days when I used it that way just like most DACs that I tried direct to my amp(s). You can stick a Schiit Sys ($49) in between the Node2 and amp to control the volume if you happen to like the sound from the direct connection.
The MastersounD Dueventi sounded superb with these speakers when I had them, but I'd advise against it if you have a large space.  I really like this series on some more romantic tube amps.
Why don't you try the Perreaux Prisma 350 ?  It sounds fantastic, runs cool, weighs 66 lbs and gives you 600 wpc into 4 ohms which would be great for your speakers.