Buying a DAC when you can't try it first

this is a generic "advice please" post.
I'm driving magnepan .7's with a primaluna evo 400 with KT150 tubes.
Most of my music nowadays it tidal streamed via a chromecast audio (CCA) with the optical output going into the DAC of a MusicHall C-DAC (its a CD player with a DAC that can be used by external sources).

I'm planning an upgrade path and leaning toward getting a DAC like the SMSL SU-9 or Cambridge DACMagic Plus and running the CCA optical through the new DAC. But i have no idea if those DAC's or something else at that price is going to improve on the musichall DAC (which some reviews say is a decent DAC).

Or should I ditch the CCA and separate DAC go the streamer route....but I'm worried that tying a streamer and DAC together limits upgrade path. However i am not totally against it. 

I'm just not sure if i even will hear anything measurably better than what I have so thought I'd reach out to you people for your thoughts and experiences. 


Cullen Cable makes a good power cord for the Node at a reasonable cost.
I upgraded from a Node 2 to Node2i, and later added a Cullen power cable. I noticed a big difference going to the 2i, and a smaller but noticeable difference adding the Cullen cord. WIth that said the Node2i (as a DAC) was still the weakest link. I upgraded recently to the Schiit Bifrost 2, and that was the breakthrough for me...natural, detailed, more extended bass. I can't compare top the pieces above as I haven't heard them, so they may be good or better, but I love the new Bifrost. Good luck. 
I have the .7's and drive them with a Parasound A21. I just purchased a RMR dac and I am using as preamp also. Love it.
@soix said it all. I second that.  I’ll add that we did a comparison of three separate streamers on the same system and the difference was quite remarkable.  Obvious improvement, well, the more you spend.
+1 On the Audio Mirror Tubadour MKIII SE DAC
For streamers, give Innous a look