Transfer Music from iPad to iMac without Apple Music

I remember when you didn't need to pay a monthly subscription ($10) to synchronize your music library across all of your Apple devices. I also remember when you could transfer songs from your iPhone/iPad to your iMac—bringing me to my dilemma.

How do you transfer a complete music library from an iPad to a Mac? I don't want to buy a 3rd party app or subscribe to Apple Music to do something Apple previously did for free.