Bluesound Node 2 - Next level up

There is a NAD 50.2 for sale.  I assume it would be a step up because Bluesound is NAD's budget line.  The Node 2 costs $500 and the 50.2 costs a few thou.  I have heard the Node 2 and consider it to have good but not great sound.  I haven't heard the NAD.

You can by a Node 1 used for around $2-300. The Node 2 DAC is a bit better, but in either case you can output to a better DAC if you like.
B

Lumin D2 is your answer, particularly if you don’t plan to run it into an outboard DAC... New price is within your budget and you can find it it used for under $2K.
I own both the Lumin D2 and a Bluesound Node2 and the analog output from the Lumin is much superior, to the point where I’m perfectly happy using it by itself. And it does DSD too if you’re into that.

For that sort of budget, I think you’re better off dividing it between a streamer and an outboard DAC with most of it on the DAC. I can tell you first hand that the sound quality out of a Node2 fed through a Schiit Modi Multibit is very good. I also tried running a Chromecast Audio ($35) through the same Modi and the sound quality was still quite good which makes me think that the DAC makes the biggest difference in this audio chain and not the streamer.

@kalali, 
I had the Modi, and it was pretty good. But, I think it is comparable to the internal DAC of the Node. You need to go to a Gungnir or Yggy to really get the best out of the music, and at under $2K used, I think it is a great value.
I do agree that outputting to an external DAC with the Node will make a huge difference.
I went to Audioconnection and John had the BS Node set up using the internal DAC and switching to an Ayre Codex. The difference was like night and day.
B