OK, a Layer-2 codec at low bitrates may sound poor today, but couldn that be improved in the future? I guess you just told me before that the encoder is not fixed in the standard.
Good thinking! As the sound quality mainly depends on the encoder implementation, it is true that there is no such thing as a “Layer-N”- quality. So we definitely only know the performance of the reference codecs during the international tests. Who knows what will happen in the future? What we do know now, is: Today, Layer-3 already provides a sound quality that comes very near to CD quality at 64 kbps per channel. Layer-2 is far away from that. Tomorrow, both Layers may improve. Layer-2 has been designed as a trade-off between quality and complexity, so the bit-stream format allows only limited innovations. In contrast, even the current reference Layer-3-codec exploits only a small part of the powerful mechanisms inside the Layer-3 bit-stream format.
