dac and streamer or seperates

I’ve just finished my journey down the same path as you’re heading now. I started with a modded Cambridge cxn v2, modded by ModWright. Excellent sound and the streaming end is absolutely seamless. I’ve never had a streaming glitch in over a year. 
I decided I wanted a little different sound and now have separates. I spent more on the dac, by a lot, and decided to go with the LUMIN u2 mini as the streamer. Great unit and it will sell quickly when I upgrade in the future. Definitely keep resale in mind when purchasing. I would spend the bulk of cash on the dac. I purchased the Rockna Wavedream and it’s a tremendous difference. Hard to tell how much the LUMIN added. Anyway, you can always spend a grand or so on a good streamer. Try to find a new model since improvements are coming fast and furious in that price range. 
Perhaps a Benchmark/LUMIN u2 mini would be perfect?

OP, just keep in mind your system when choosing a dac. The Krell is apparently sensitive to what it’s paired with, based on the reviews I read. Very powerful unit. Also, B&W speakers have a certain sound. Do you want a dac like a Denafrips, r2r, or tube to add a bit more relaxed and natural sound? Or do you want something a bit more analytical? Think of what you currently have and where you’d like to be. How much money you spend is certainly important but what’s more important is not wasting money. I’ve made those costly mistakes because I wasn’t sure what I wanted and just tried things. Take your time and be honest with yourself about the sound that your ears and heart love. Good luck

A good one yes. Many people like to balance solid state with tube preamp or dac. Again, it depends on the sound you’re looking for from your system. I’m biased, I have a tube amp and preamp. I recently changed to an r2r dac, no more tube dac and really like the balance of detail, clarity with just the right amount of smoothness. I don’t like overly romantic sounding gear or highly precise, technical gear. Keep in mind that I’m all digital, no vinyl. I need to tame the digital a bit. If you listen to mostly vinyl, you already know you like that smooth, easy sound. Try as much gear as possible so you hear different parts of the romantic to analytical spectrum as you can. I think the right dac can make the system. Shop wisely. 

Good post malbers. I really did not expect Paul to feel this way. Glad to have affirmation for my recent decision. 😀

OP, I’m pretty open minded when it comes to this hobby. I had solid state for 25 years and have recently gone tube amp and preamp. I’ve owned 3 dacs and demoed another and let me say with 100% certainty, BITS ARE NOT JUST BITS. Any simple test and you will quickly see this is not the case. Shop wisely.