MP3 Audio Quality for Single and Multiple Encoding

The results of several measurements of audio quality of single and multiple MPEG-Layer 3 encodings will be presented. Subjective and objective tests have been done. A comparisons between the scores of the objective difference grade (ODG) and the subjective difference grade (SDG) prove a more accuracy of the PEAQ method at higher bit-rate. The recent versions of the LAME encoder and PEAQ software based on the ITU recommendation have been used, in association with the ITU standards for the execution of the Subjective test for small impairments.