Separate Dac, and what kind?


I believe a separate dac would improve the sound quality of my system, but I simply don't understand much on the digital side of equipment.  I have a sonos connect (for wifi streaming from router in other room), and a 15 yr old Sony scd ce595 connected to relatively new bryston bp6 preamp and bryston 3b cube amp.  Speakers are aerial acoustics model 6.  Blue jean cables, interconnects.

There is no digital input for a direct connection on back of sonos for an Ethernet from router in bedroom to the sonos in the living room (its a 45 ft run, and I don't want to bother with wiring anyway).  I mention this because a hard connection might sound better.  I have to use the sonos wirelessly for a streaming connection.  It only has digital and analog out.  Of course I use the analog out since I am using the dac in it.  The cd is connected directly to the preamp (again using dac in cd).

I don't mind spending $1500 on a new piece of equipment.  I am considering shitt.  I listen to jazz mostly since the recording are always better than rock, pop, blues etc. (no symphonic music), whatever the source.  And I used to play jazz, big band.  This equipment is very transparent, I sent back a new bp17 because it had a somewhat synthetic quality to it (thought I would mention this, Im striving for an organic natural sound).  Any suggestions?  I would appreciate any ideas.


crossfree
I hate to berate a product, but I think you can do better than a Sonus.
For the money, Bluesound offers the Node which does what the Sonus does, at an equivalent cost.
The nice thing is the Bluesound allows you to use an outboard DAC, so you can really up the sound quality.
Unless you need 5ghz band wifi, just buy a used Node ( I added a Netgear router to move my Node 1 to 5ghz).Even Bluesound said I shouldn't move to the newest Node.
If you really want to go to the next level, try Aurender. They will be offering a streamer that will allow you to connect to another Aurender, soon. I heard the difference between the Bluesound and the Aurender via an Ayre Codex at my dealer. It was quite significant.
Bob
+1, jl35.

Don’t waste your money on a new DAC unless you upgrade your source. If you love Sonos app (just as much I do) then Wyrd4 Sound upgrade is a must.

Bluesound Node or Aurender N100 ( if you can afford it) will get you much better sound even beyond upgraded Sonos box. 
So, I was reading about the Node 2i at crutchfield. Nowhere does it mention it has a dac built in. Does it?

lalitk, you mention the node is superior to even the wyred4sound upgraded sonos, but once the sonos is upgraded it's just a transport for the digital signal. I assume you are saying, no matter what kind dac you pair with an upgraded sonos, bluesound node 2i is better SQ?
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The Bluesound Node 2i includes a DAC and it’s pretty decent and will pass through MQA if that matters to you.