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. 

....sigh.

mid-fi-crisis
That  TUBADOUR III Non Oversampling Tube DAC sounds interesting.  How durable are the tubes?  Are you replacing the tubes frequently?

I purchased a BlueSound Node 2i and was talked into adding a ProJect S2 DAC and I thought it sounded thin compared to just the Node 2i.  I also play Tidal and for some reason I think I hear a difference when playing MQA or is MQA just a gimmick?  I would think some remixes are better than the original?  Can your really hear a difference in DAC's?  That might be something to explore next.
I would second what most are saying.  Don't cheep out on the DAC.  Personally, I would have just gone with something like a PS Audio DirectStream Junior.  It has a built in streamer and wonderful paired with Roon.  The warm sound that it produces, brings it really close to sounding like analogue.  It nearly matches my analogue front end that cost 4 times more!

You might be able to find one used for $2-2.5k. 

The Lumin streamers are also highly recommended and come with built in DACs.  Only thing is most of them don't offer inputs, if that was a consideration.  I've not heard a Lumin, so don't know.  Just have heard they are highly recommended when a single box streaming solution is desirable.  

Outside of that, I might consider something like a Chord or Mytek DAC.  Once you want to go beyond that -- say a DAC of $4 - 5k -- you need a big price jump. And probably paying for the output stage.  The money might be better spent on upgrading amp or other. 
@larry5729 The stock tubes are rated for at least 5000 hours. I'm getting close to a year into daily use and my tubes sound better than a brand new replacement pair I have in storage. Replacements of the stock tubes are plentiful and something like $40 from Audio Mirror.
Chord Quetest is the Dac to beat under $2k . Add a good streamer like Auralic Aries G1 and whamo! And don’t forget some decent cables.
Just another thought: I replaced my older DAC with the Schiit Yggdrasil ($2,449) and was favorably impressed that it delivered so much for such an affordable price.   (plus fully balanced from input to output)  Highly recommended by Stereophile and TAS.