Adding audio files to your MP4 video project.
Unlike video MP4 files, MP3 files are used for music and hold smaller file size audio tracks. Easily convert audio files to MP4 by using Premiere Rush — add files with narration or music to your video project before saving them as an MP4 output file. The MP4 format is desirable for its versatility. MP4s have little loss of quality at a higher compression and MP4 files work on nearly all media players — a good way to get your digital audio on more platforms.