Here's how I do it. I love real songs as my ring tones, my current is "September", from Earth Wind & Fire (think the party screen at the end of "Night at the Museum"). So here are my steps, all free, no software to buy/acquire, all native to the Mac:
- From Youtube, find the song you like in a rendition/quality you like. Use a downloader to download the MP4 from that page. (I use the Parallels tool downloader to get the MP4, anything will work)
- Create iMovie project - add the MP4 media. Under File/Share/File, save "audio only" as MP3
- Import MP3 into Apple Music
- For the file in “Recently added”, go to Info/Options - make it up to 40 seconds long - pick the right part of the song for a ring tone (listen to it)
- Change the title etc. as desired
- When happy with the clip, File/Convert/Create Apple Lossless version
- Go to Finder location, copy file to desktop, and change the m4a extension to m4r
- Go back to the original song, to Get Info/Options, and uncheck the start/stop that created a 40 second version if you want to keep it in your Apple Music Library
- Connect iPhone to MacBook Pro. Make sure the Finder window is on the General tab.
- Drag the .m4r file to the pane under the General tab in Finder, for the phone - wait until a very fast progress bar completes at the bottom of the pane
That’s it! Go to Settings/Sounds & Haptics/Ringtone, (Settings/Sounds/Ringtone on iPad)and you will see the new ringtone there!