What is the best place to archive my digital music files?

OP

your original post is to short on information.  What is your current source for your digital files?  Does your Marantz amp come with a streaming module?  Does it have an included DAC?

  If the answers to the two questions above are yes, then does the streamer-DAC accept Qobuz directly?  Or are you using a PC that is attached to the DAC by USB?  Or sending Qobuz from a portable device to the amp by Bluetooth or AirPlay?

  Regarding your iTunes files, presumably everything in there is available in Qobuz.

If you ripped CDs or saved downloads into iTunes, and you want to keep a physical copy , just keep whatever device you are currently storing them in , and make sure that you have a backup.  If you were to add Apple Music, then all your files will appear there.

Your post is a little vague, but the “best” place to store your digital music files is on a solid state drive.  You can plug into the Marantz’s USB port and presumably play from there.  I picked up a very cheap 8 Tb USB drive, to which I back up all of my music from my server and in an emergency, (like a potential hurricane) can grab it and put it in my pocket, just in case.

Thanks to everyone on this thread.  I will confer with a specialist at Audio Advice and come up with a hardware plan. Really appreciate the help.

I can almost guarantee that if you would’ve been more forthcoming about what your situation was, you would have gotten a much better response from this community. Thinking that a 20-year-old kid is gonna have the vast wealth of knowledge that is on this site… Good luck! 

gkelly- Your first and second responses were very helpful and will lead me to find a good solution.  Let's just leave it at that.