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Can I use a Music file as a ringtone my Samsung Galaxy S® 4?
Your device can add a music file, such as an MP3, as a ringtone.
Create a Ringtone
To set the music file as a ringtone, from the Home screen, press Menu > Settings > My device > Sound . Touch Ringtones and then touch Add at the bottom of the screen. Quickly double-touch Sound picker and locate the music file you wish to use. You can set the entire music file as the ringtone, or have the device auto-recommend to play the best part. To use Auto recommendations, touch From the beginning at the bottom of the screen. When you have made your selection, touch OK to set the ringtone.
Tip: Touch the file name to preview the music file and touch it again to pause.