Subjective testing of MPEG-2 NBC multichannel audio coding

This paper presents an overview of the preparations for, and the results of, the subjective listening tests on the new MPEG-2 non-backwards compatible (NBC) multichannel audio coding algorithm carried out by the BBC and NHK during September and October 1996. The codecs tested were: MPEG-2 NBC at 256 kbit/s, MPEG-2 NBC at 320 kbit/s, MPEG-2 NBC low-complexity at 320 kbit/s and the 1995 version of MPEG-2 Layer II at 640 kbit/s operating in a backwards compatible mode. The results showed good performance for all of the codecs. The MPEG-2 NBC codec at 320 kbit/s generally performed better than the other codecs and, although not quite transparent for a few test excerpts under these rigorous conditions, it passed the EBU criterion for “indistinguishable quality”. The MPEG-2 NBC low complexity version at 320 kbit/s was, by a small margin, not quite as good as that of MPEG-2 NBC at 320 kbit/s