Can I produce and sell polyphonic ringtones for mobile phones without having of copyrights for original songs? I can convert MIDI files to polyphonic ringtones. The MIDI files contain only instrumental music, not vocal performances. Therefore the polyphonic ringtones contain only part of the original songs ( Instrumental ). Also the instrumental music in the polyphonic ringtones is not completely the same with the instrumental music in the original songs. Can I use parts of songs for creation of polyphonic ringtones without having of copyrights for the songs ?