B&W Nautilus 803 or B&W 702 S2?

Did you ever end up picking a pair of speakers? Interesting thread as I keep going back on forth on the same issue. I heard the 702 s2 and really liked them. I think they are very good for the money. Something keeps me wanting the d3 series instead but really not sure for me if its worth the extra money.

Im a newbie to the world of audio so forgive my lack of correct lingo and understanding of it. :-)

I used to have a pair of b&w cm10 s2 paired with  a intergrated amp rotel ra-1570 I bought 2 years ago & Chord 2qute dac until one speaker was damaged .  

I was sent a replacement set of the b&w 702 s2 without having ever heard them . Now I realize what an amplifier does and the difference between them and intergrated amps! Yikes 🤦🏻‍♀️ 

So now im wondering where do I go from here ? I thought the speakers sucked until my friend hooked them up to a class a amp and a Velodyne DD18subwoofer . So QUESTION IS .. 
What kinda power amp can I buy to power these 702 s2's without killing my piggy bank? Had no idea audio equipt was so so complex ! 

I'll put a couple suggestions that have already been recommended a lot.  The Hegel H160 will be a better and more refined integrated than the Rotel for about $1600-1900 used.  The H300 will be better than that, as the B&W speakers really need a high current / high power amp.  Other options could be the older generation Emotiva amps with a fuse upgrade (such as XPA-1 gen 1, or any of the XPR series).   Parasound A21 would also be a nice amp, and also works great with fuse upgrades.

I highly recommend a tube preamp partnered with a Wyred for Sound ST 500 amp.  I have B&W N802 and Concept 90 speakers.  This combo is killer on both pairs.  
Beware of all the hearsay recommendations from people that don’t own B&W speakers.  My 2 cents.

Hi  chief4425, I ended up holding off on speakers for the time being and decided to put my efforts into upgrading the amp.  I went with a used McIntosh Mc205, got it in May.  It sounds amazing and couldn't be happier.  I still have the old Paradigm 60 v3 - have had them for 15-16 years.  I can't believe how great they sound and can only imagine what a properly chosen speaker(s) will be like.  We will be going to the RMAF (Rocky Mountain Audio Fest) this weekend and will be looking at several speakers.  Anyone have any suggestions on speakers other than B&W, Focal (I plan on those already, along Zu Audio, and Tekton)  Any suggestions appreciated.