MP2 and MP3 or MPEG1, layer 2 and 3 is a kind of psycoaucoustic coding that removes up to 90 to 95% of the original signal(!!!)
The MP3 standard is defined by Moving Pictures Expert Group(http://drogo.cselt.stet.it/mpeg/) in cooperation with ISO and IEC.
Layer2 compress the signal to between 6:1 and 8:1, Layer3(MP3) compress 10:1 - 12:1. Theoretically this means that Layer2 sounds better(because of the lower degree of compression) than layer3(MP3). Howerver, download time for MP3 is significantly lower than layer2
Yes but can you hear the difference between mp3 and mp2? I can hear it between mp3 and cd quality but i have very minimal background in mp2 technology. Is it like mp3 and cd's only some people notice it and others don't?
From what I understand, there is little difference in terms of quality, rather just file size.
They both sound good, but mP3's are able to reproduce an equal sounding result, at a lower bit-rate.
I'd imagine the encoders have advanced somewhat since mP2 as well, as they also progressed even just with mP3's. For example, the evolution from mP3 Producer Pro when mP3's were first introduced, to the now highly acclaimed Lame encoder further down the line which produces much better results, even though it's the same file format.