Im not good in music / ringtone.Just found this simple cutter at google.
Credit:-
mp3splt
Usage:-
1. apt-get install mp3splt-gtk
2. Install GStreamer extra plugins via ( Ubuntu Software Center )
3.Right click at your *.mp3 file then Click mp3splt
4.Click Play button and click +Add and click +Add again depends on which you want to cut.
5.Click Split on top of the program and you might find your file at /home/
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