I believe you are correct about the Apple TV downsampling Hi-Res files, that is why i suggested using it if you are playing ripped CDs on your computer. I have never played any HI-Res files. I stream my ripped CDs wirelessly to an Apple TV or Airport Express because my iMac is in my home office and my systems are in different rooms. I use my iPhone or iPad as a remote to access the files on my iMac. I think the SQ is great with either the Apple TV or Airport Express. When I did try USB directly out of my iMac to any of my DACs, I could not detect any difference compared to streaming wirelessly to the Apple TV using the optical out into the DAC.
I found the SQ of streaming my ripped CDs to an Apple TV or Airport Express to be as good as using my CD players. I have since sold off my CD players and play all my music from my ripped CDs on my computer. It is just so much more convenient. Even my 3 year old grandson uses his iPad to play music on my wife's system when he visits.
My son's system is more expensive than any of mine and he still uses the Apple TV and hasn't found anything better that works as simply at a reasonable price.
I found the SQ of streaming my ripped CDs to an Apple TV or Airport Express to be as good as using my CD players. I have since sold off my CD players and play all my music from my ripped CDs on my computer. It is just so much more convenient. Even my 3 year old grandson uses his iPad to play music on my wife's system when he visits.
My son's system is more expensive than any of mine and he still uses the Apple TV and hasn't found anything better that works as simply at a reasonable price.

