Streamer upgrade


I need recommendations for a new streamer that will replace my Sonos Connect.  The rest of the system, developed largely from AG recommendations, consists of Fritz speakers, driven by a Primaluna EVO100 integrated. Sources are a Clearaudio Concept table and Cambridge Audio CD transport through a Schitt Bifrost (also handling DAC duties for the Sonos).  I'm using Amazon HD as a streaming source right now.  This system doesn't need to integrate with  my other Sonos speakers.  It's my intention that this be an end-game system, so I'm looking for a streamer that's appropriate to its level rather than something that's going to lead me down the path of perpetually upgrading other components.  Price is a secondary concern, used gear is fine.

Thanks for any advice - truly appreciated, and I'm grateful for all of the forum help I've received in the past.
philiptamarkin
+1 on opticalRendu 

I have been using one for more than a year in my main system and find it to be a substantial improvement compared to Node 2i in my office system. Its calling card is a much lowered noise floor.

But if cost is not an issue, also consider Lumin U1, Aurender N10, Sonore Signature Rendu SE, or Wolf Audio Luna R. I'm leaning heavily in the direction of Luna R Digital if and when funds become available.
I started with a microrendu and then made my way up to the top of line signature renduSE optical. I think it all depends on your budget. I thoroughly enjoyed the microrendu. The more expensive units do add to the sq but you pay for each step. Btw, in regards to the upper models, I thought the optical rendu was very very close to the signature rendu se optical so if you did want to increase your budget I think you can stop at the optical rendu, a true reference level streamer. I also second the small green computer for their I5 Roon core server. High quality and good support. You can add additional sq by using a quality linear ps for the server and rendus. Plus I’ve seen all of these on sale used 
Lumin  -- I have had the D2, A-1, X-1 and just purchased a U-1 mini. There is one for any budget but if you can step up the X-1 is definitely reference quality Dac/Streamer.  The app is super easy to use.  You do not need Roon or JRiver.  I know there is a thread devoted to the Lumin X-1.  You should read it.
" It’s my intention that this be an end-game system, so I’m looking for a streamer that’s appropriate to its level rather than something that’s going to lead me down the path of perpetually upgrading other components"
So one box ? streamer/dac/managment software?
I am still riding the separate/tinker bus. I like the flexibility of being able to upgraded or change each stage. There is so much good stuff to be had out on the used market. Giant audio flea market at you finger tips. Cuts both ways as I did sell a pair of speakers I wish i had back now :(
You kinda already taken the first step by stepping out of the Sonos connect and adding the Bitfrost.