Multiple audio systems in different rooms; how to link them with streaming gear?

yes i think the best answer is a bunch of nodes

sonos connects work too, but sounds poor if you want real hi fidelity sound in multiple locations

good news is nodes (esp the older 2i models) are very inexpensive used these days, trading at 300-400 each...

I do this in my home using ROON and Powerline adapters for multiple rooms.

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I also use fibre optic at the last few feet just before my DAC to clean up any gremlins showing up in the chain.

The only issue with this, and likely not a concern for almost everyone, is do not put the ROON core server on the side of the PowerLine gear if you are streaming hi-res. The best place to put the ROON core in close to the router or anywhere with a direct Ethernet connect to the router. The bandwidth on the Ethernet is much higher than the PowerLine. Listening to the hi-res on the PowerLine side is fine if the Core server is on the Ethernet side.

The sound I have on each ROON endpoint is fabulous. I only do fibre streaming, but use copper to get me to the fibre.

@av_affected 

I haven’t tried anything else nor have any inclination since switching to SONOS eco system about 16 years ago. My house is wired with 12 SONOS speakers, sound bars plus subs, all you need is a power source, plug n play and SOTA app that plays music from variety of apps anywhere in the house. There are ofcourse cheaper alternatives, but if you value high quality sound and longevity, the initial investment is worthwhile. 

I use roon, one is wired, one is wireless.  they sometimes get slightly out of sync and I have to stop and start.  I'd look to fix this but I do i very seldom.  Just thought I'd mention it as an issue you may need to deal with.