CVU file is a CVSD Unfiltered Audio. Continuously Variable Slope Delta modulation (unfiltered) is an alternative handler for CVSD that is unfiltered but can be used with any bit-rate.
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.