Apple’s desktop platform is home to a vast library of creative software, like image editors, vector graphics suites, RAW photo processors, audio manipulation software, video editors.
And then, of course, there are digital audio workstations (DAWs) for making music.
But owning a Mac doesn’t necessarily mean you’re swimming in cash, and music production suites can run into thousands of dollars. The linked article below looks at how you can start making music without spending any dollars.
See http://www.makeuseof.com/tag/best-free-mac-digital-audio-workstations-daws/ 
6 Best Free Mac Digital Audio Workstations (DAWs)
You don’t need a Mac to make music, but with this much free software available it certainly helps.