Why MP3 compression does not influence the sound quality?
The basic principal behind MP3 compression is a technique called perceptual noise shaping is used. It uses characteristics of the human ear to design the compression algorithm, for example: • Some sound are not loud enough to be heard; • If there is two similar sound at the same time point, then the weaker one will not be heard; • Human ear have better response to certain sound than others; So thess certain parts of the music can be removed without causing any noticeable difference to the human ears. Although in principal MP3 file can be of no difference to human ear compare to the original CD files, no practical compression algorithm can gurantee 100% conform to these principals, so we always obtain a near CD quality Song.