Music server recommendations needed.

+1 on the Aurender ACS 100. Excellent unit, built-in CD for ripping and encompasses a very good streamer. Easy to install and excellent library management. I have 14TB (max 16 TB) of music loaded and no hick ups. If I remember correctly, that is close to  20,000 albums. Large screen to display album artwork and track being played. Also, it is reasonably priced and they have excellent support team for answering questions. Good luck.

I have a collection of 4000+ CDs that I ripped to uncompressed FLAC. I'm going to focus on the ripping process because you may not have realized how many hours it will take to rip your library.

My main goal was to rip as quickly as I could with the best quality possible. I used a ASUS gaming laptop equipped with an external CD drive I built from a Plextor PlexWriter PX-891SAF which is a robust drive that will rip CDs at the fastest rate possible. I used an OWC Mercury enclosure. The difference in ripping time was multiple times faster than using the internal CD drive of my computer.

The software I used was dB Poweramp which has a few important features. You can rip to uncompressed FLAC which is the closest thing you can get to a standard WAV file but FLAC allows you to tie metadata to your ripped files. The uncompressed FLAC files are large but hard drive space is cheap. By using no compression the computer/player that plays the file doesn't have to work as hard. I don't know if this has any effect on SQ but I quickly determined that I was only going to do this once and I wanted to ensure that I had the best quality file I could get. The program will also decode HDCD files and rip them to a higher bit level (you have to go into settings and click the option). It automatically retreives the album cover and names the songs so your folder has all of this information. It rips to a hard drive which you can then back up to another drive or two for safety. I promise you, after spending hundreds of hours ripping your CDs you will get very paranoid about losing that data. And lastly, the program checks your rip for accuracy against its database and if it isn't 100% accurate it will note that for each song so you can rerip if you so desire.

The PC/Plextor system will literally save you hundreds of hours of ripping time. I don't know how fast a server/ripper will do a CD but I'm pretty sure that it is much slower than the Plextor. I have the computer and CD drive set up on a small table by my listening chair and I ripped a stack of CDs every time I sat down and listened to music. It took me a couple years to get through my whole collection. If you have a server/ripper positioned with your other audio components, getting up to change the CD in the ripper is going to get old real fast.

Once you have your ripped files on a hard drive you have complete flexibliity for how you want to play them. Depending on how much flexibility you want you may not even need a server. I plan to get an Eversolo DMP 8 which can use an internal memory card for ripped files (I will transfer these from the hard drive). Since I don't need to access my stored files in other rooms I think this will be all I need to do without the complexity of having a server.

Surprised nobody has recommended a Roon server.  I personally love it's  metadata management and deep search capabilities. It also fully integrates you library with Tidal and Quobuz, so you can have the best of both worlds. Have a look if you are not familiar.

I had a Roon server and replaced it with the Esoteric N-05 and that’s what started my Streamer merry go round. I will keep my Evo432 Aeon Mk iii until I find something more than marginally better.

Nobody mentioned Rose which has a couple of nice options.

SACD? No straightforward (legal) solution...

Only Qobuz? I still prefer my local library, but why not have both?

Last, I believe in the 2 PC setup with a minimalist and quiet endpoint. And while I have all diy based on standard components but powered by linear power supplies, I would just use a normal PC (with HQPlayer and Roon?) as a server and a Sonore endpoint if I would go commercial. Use an EtherRegen to quiet down the network between the 2 components. Simple and cost effective but on same level as insanely priced Gucci stuff