Ready For Digital Source...Computer?

Wow, auxinput, all that computer stuff is a little bit over my head so maybe I better just stick with the music server solution, but thanks for all that.,,very interesting indeed!

Yes, that's another good reason to buy a server. I was an IT executive... so I was good fiddling around with computers... or if I had a real technical issue, I would call one of my tech guys to fix it. It is pretty easy to set everything up, then find out a switch somewhere wasn't thrown and you were limiting you output resolution. 

An older windows laptop and a good dac are a great choice for folks with lots of music on hard drives.  Use Foobar2000 and the related Foobar2000 remote control for smart phones and it is super convenient.  Set up Windows sharing across your home network and you can also use Plex if you wish though I don't like it as much since it doesn't allow selecting WASABI or ASIO to by pass Windows audion settings.

in place of Moon, you might want to consider Hegel integrated amps. I use a Mac and Audirvana. When Audirvana works, the sound is divine. 

I’ve streamed airplay (via Mac mini) to a Hegel h590 and found it to be superb. It also works with quobuz, Audirvāna, Roon. The Hegel HD 30 DAC works as a streamer and DAC with volume control and digital preamp. The simplicity is amazing. 
most of my music is legacy cd, streamed from a synology server in my office. 
I didn't see enough of a difference with high bit rate quobuz audio to pay every month. 
there is also a challenge with playlists. Most can't import them. And if you choose to move on to another service, your playlists don't come with you!

as such, I still value Apple Music (iTunes) for the metadata capability.