Two DACs for one system?

OP's question is a bit ambiguous but neither the Node2 nor a CD "player" require an external DAC. That been said, I guess one could argue that these devices could potentially benefit from adding an (external) DAC between them and the preamp. Even if that were the case, you'd need separate DACs for each if you want to be able to switch sources using the preamp vs. swapping cables.

I agree that an external DAC could better playback from both units. To what extent depends on your system. Please provide more info on your system. 

What @jond said. The DAC in the Node 2 is pretty good all by it's self but certainly can be bested if you want to spend the money. I've not heard your CDP but no doubt it can also be bested with an external DAC. I would recommend becoming very familiar with the sound quality of your newly acquired Node 2 (?) before acquiring a new DAC, you might be pleasantly surprised. I purchased my Node 2 back in April btw .. love it. Enjoy.

Marantz cd 5005

What is your cd player? I think perhaps what folks are telling you is your cd player, and your Bluesound Node might both benefit from a better external Dac. You could then plug both your sources into that Dac and reap the benefits either streaming or spinning CDs. That's how I interpret what you are saying and asking.

I looked at the Bluesound Webpage. It looks like it connects via Ethernet and then outputs to either RCA or Toslink.
So, Yes, I think you need a DAC for your cd player, if it is only a CD transport and not a CD player. The former only plays the CD, the latter plays and deciphers the signal to the preamp.

Should you need a DAC, I would suggest a Schiit Modi or Bifrost Multibit. 
Both are quite inexpensive and will provide you with excellent sound.
HTH
Bob