In this Article you will learn about MP3 vs M4A. .MP3 files can be encoded at a constant bit rate or variable bit rate. A constant bit rate ensures the same quality throughout the audio file but results in higher file size. Variable bit rate detracts from quality during silent or near-silent moments of a file, resulting in smaller overall file size. Whereas .M4A is an Apple-based format that corresponds to .MPEG-4 video files. .M4A files feature lossless compression, allowing for multiple edits without a loss of quality. Compared to the other audio file formats on this list, .