Very much so. I-M4A yi-MP4 equlethe i-AAC okanye i-ALAC enesandi — emiselweyo ye-iTunes neefayili ze-Apple Music. That determines both the headroom available and whether the saving costs you anything in fidelity.
Yes — i-.m4a ingagcina i-AAC okanye i-ALAC, ngoko iifayili ezilahlekileyo nezingalahlekileyo zisebenzisana noluhlu olunye kwaye kufuneka zicaciswe ngokuhlukileyo ngokujongwa. It is worth knowing before you overwrite an original you might need again.
Yintoni impazamo eqhelekileyo xa uxinzelela M4A audio files?
No. Cima M4A is free without an account, and nothing is added to the audio. The upload and the result are deleted automatically about 24 hours after the job, which leaves time to download the result.