I've had a difficult time doing a similar thing except I'm trying to put the music files on an external SSD. There are a variety of instructions in the web but they all seem different and some don't seem to work. However I think I have it working. I'm running Catalina 10.5.5 and can't say this works in any other version.
Before you try this, MAKE SURE YOU HAVE GOOD BACKUPS!!
There are three major steps:
Step 1. Create a new music library (the old library is likely called "music library.musiclibrary"). This should avoid ending up with duplicates in the library and will allow you to easily delete the old music files from your internal drive.
Start the Music application holding down the "option" key. The application will then ask you if you want to create a new music library.....
Step 2. Go to Music Preferences>Files. Mine set up as shown below. The "Music Media folder location " is a pointer to a folder where you want the actual music files to be. By setting it to somewhere (using the "Change" button) other than the default setting, you're telling the system that the new location is where the actual music files are to be stored. You will likely want to point to a folder on your server.
- Note 1: Apple still says "Music Media" on this window. This is not to be confused with the "Media" directory buried within old iTunes folders or default Music folders created by the new Music application.
- Note 2: It seems important to have the two checkboxes checked.
- Note 3: The button "Import Settings" here refers to the settings for importing from a CD. It does not apply to the "Import..." selection in the Music "File" drop down menu which I use in step 2 below.
Step 3. Now, having pointed to a new location for the music files, you have to actually move them there without messing up all the pointers hidden in the mess of files Apple has lying around. The current location before trying this is buried, possibly in different folders within Music and/or iTunes folders in your home directory (within "Users"). In this step, you will use the "Import..." selection in the Music "File" drop down menu. With the "Import..." selection, you will be guided to point to the music files you want to move to the new location you've set up. Those files are probably organized as shown below. Note that the screen capture shows the layout on my external SSD "Media Drive" after I've completed this step.
You can select a group of the original music files and they will all import to the new location at the same time. You can repeat this for each location where you find original music files.
At this point you should have everything ready to test. Make sure you test syncing to your iPad or iPhone etc. Once you're satisfied, you can delete the music files from their old location. And delete the old "music library.musiclibrary".
If you have a problem, not to worry, you made backups before you started.
Hope this helps.
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