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.
WAV is an audio file that is associated with Microsoft Windows. It is the default audio format for Windows. But it supports almost all the Operating Systems. WAV files are comparatively larger than MP3 files. It is mostly used to create music files in audio cd. It can save music files at different bit rates.