In our main listening room we are looking for a Roon Bridge to accept Ethernet and pass the full digital audio signal to our McIntosh MX121 AVR (with DAC). Available inputs on the AVR are Optical, COAX, and HDMI.
We are contemplating an Mac Mini, but it only has HDMI, so we are looking for some other options that may provide a quality pass through to the AVR.
Mac mini also has mini TOSLINK optical integrated within the 3.5 mm phone jack. But Mac mini is overkill for just Roon Bridge. Unless you need a multipurpose computer in your equipment rack, simpler Linux solutions are available to run Roon Bridge.
I use a Raspberry Pi with HifiBerry Digi+ Pro HAT in a similar setup. The Digi+ has coax and optical out and accepts up to 24/192. It’s fine if you don’t intend to do anything with DSD. https://www.hifiberry.com/products/digiplus/
There are lots of higher-end options, of course, but it’s hard to beat for the price.