Emphasis on stereo but need a complete solution.

So I started trying to fix my stereo output from apple music and have ended up realizing I need to replace the middle of my system.  I only have two real sources of audio video, Firestick and a streaming music service.  

For tv/movies, I don’t care all that much.  Mostly watch baseball, nice if movie sound is decent. Only source is Firestick 4K

For stereo, I do care.  I want the Totems driven as well as possible.  Source Tidal, Qubuz, Apple???

I have a 30 year old NAD 2 channel 2100 amp- I could use for the Totems but willing to replace.

Also have Yamaha – RX-V375 Receiver which I could use for the surrounds.  I don't want it in the signal path to the mains (Totems)

So I care most about the DAC, Preamp, and 2 of the 5.1 channels of the amp(s)

Would rather have the amp(s) separate from the digital stuff.

I used to know audio but stopped paying much attention years ago and somewhat confused by the digital side.  I am a programmer but just don’t keep up with audio formats much.

Cost is definitely a factor.  Used stuff is ok with me and usually more cost effective.  Would like to stay under 3k-ish.

I think I’m breaking the problem down correctly but chime in if not.  Mainly just want to figure out how to break out the components.

What do I put in the middle where it says  ***(What goes here???  

Existing system:

Video source:FireStick 4k  ->  

TV:  4K HDMI Input ->  Sony 85" Class X90CL Series 4K  -> 4k HDMI output ->

***(What goes here???   Decode HDMI, Streams Tidal, preamp, amp) ->

Mains: Totem Winds for left/ right mains  - 80-250 watt, 4 ohms, 87 dB sensitivity, 24-21 khz +-3db

Surrounds: Energy center, rears  -No specs, decent, not very important to me

Active Sub (maybe removed if the Winds can handle the lows for movies, don’t need sub for music)