무료 온라인 IRCAM에서 M4R로 변환기

IRCAM SDIF (Institut de Recherche et Coordination Acoustique/Musique Sound Description Interchange Format). Used by academic music software such as the CSound package, and the MixView sound sample editor.

M4R - is a digital multimedia container format used to store audio in mono channel mode. This format is suitable for store ringtones and it is widely used by Apple iPhone for its ringtones. Needless to say that M4R and M4A formats shares many similar features.