M4A to M4R -- easily convert m4a to m4r
Easy Way to Change M4A File to M4R File
If you want to set m4a files you like as your iphone ringtone, M4A to M4R Converter can help you convert m4a files to m4r iphone ringtone files. What's more, the Converter supports converting almost all mainstream video/audio formats including AVI, MPEG, WMV, DivX, MP4, H.264/AVC, AVCHD, MKV, RM, MOV, XviD, 3GP, WMA, WAV, RA, M4A, MP3 to M4R iPhone ringtone.
Firstly you need to install the Converter into your computer and run it.
Secondly you can click "PC to iPhone " button
, then click "Add File" to import M4A files into the software.
M4A to M4R Converter provides editing function. You can clip any music segment from video/audio file and turn it into iPhone ringtone. Drag the two sliders or change the number to reset start time and end time. Play button is to pre-listening to the added music.

Thridly set the destination folder. Click "Browse" button to change Local Output File settings. Click "Import" button to convert to iPhone ringtone directly.
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All right, you have successfully convert m4a files you like for your iPhone. Come on to try. It will bring you more surprise.