Convert mp3/wav to MIDI format?

I have a samgsung gravity T456 and i need to convert mp3 to midi in order to have te mp3 song i want as a ringtone. ive looked and tried out some of the converters but it doesn't sound the same.. is there any converter than can convert form mp3 to MIDI without change in sound quality? as in having all instruments on one midi file

Suggestion:

ventones.com