My Marantz Amp is Roon Ready and the Roon App (both the desktop and the iPhone version) is pretty good and sound quality is amazing as the App streams the files bit perfect without any downmixing, via ethernet.
Roon unfortunately doesn't handle DVD-A and DTS formats properly. I use Plex server and Infuse running on the Apple TV for those, and they work well. (Yes, I know I can convert .dts files to multi-channel FLACs using ffmpeg, but too many files, and I have not gotten around building an automated conversion workflow)