Background. Right now I use Tidal through Audirvana on mac to lavry da11 via USB to integra receiver. 60% of the time Direct [stereo no sub] ,20% stereo W/sub , 20% all channel stereo [front left right, rear left right, and sub]
I’m getting either a nuc i7 or nucleus. Open on endpoints. Best resolution a plus. Looking at updating dac to Mytec Brooklyn DAC+ which has dual outputs and solves almost all of my problems 
I’m trying not to drop 2k ontop of the cost of getting Roon.
GOAL ONE. Playing my stereo pair of speakers via Roon, any endpoint to lavry da11 to mono blocks to speakers. With dac doing volume control.
GOAL TWO. Turning subwoofer on and off at will either using a second endpoint or most likely a remote controlled power strip W/ subwoofer connected via high-pass input from mono blocks.
GOAL THREE. Turning on and off at will rear stereo pair synchronized with fronts via any endpoint through any dac W/ volume control to stereo amp to speakers.
I’ve been looking at raspberry pi with hats as endpoint. Can one pi feed dac and stereo amp W/ volume control? + sub switching each on or off at will?
Can you sync two mini rendu or raspberrypi? One feeding lavry da11 the other feeding cheapish dac w volume control via Roon to stereo amp?
3 mini rendu or raspberry pi one with cheapish dac to run sub w volume control via Roon?
I hope I have asked the right questions. Any input would be appreciated!!!