Download this M4A to M4R Converter, install it and run it.
Step 1: Load M4A files by clicking "Browse" button on right above of the M4A to M4R Converter software interface. ![]()
Step 2: Click "Play", listen to the music and select your favorite segement . Then drag the start & end slider to clip the musi or reset start & end time in the corresponding text box directly.
Note: Pre-listen the M4A music before converting to M4R file to ensure it is just what you want.

Step 3: Set the output destination folder to save the converted M4R iPhone ringtone by clicking "Browse" button.
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Step 4: Click
to converting M4A music to M4R .