Without a specific label on the "new" version, we have to make two assumptions. It is likely either:
Ironically, a greatest hits album is the worst possible way to hear a band's journey. The Black Album is polished hard rock; Kill ‘Em All is raw punk-thrash. On the "New" digital files, the volume levels between a 1983 track and a 1991 track are identical due to remastering normalization. This is historically inaccurate. metallica greatest hits pbthal 2496 flac v new