Kill 'em all voice was an uncut jem. In Ride and Master his voice had that haunting crystal echo that matched the songs perfectly. AJFA still had that crystal effect but was more powerfull, strong and brutal. In Black Album he lost that crystal effect but still had the power and the brutality, although tuned down because of Bob Rocks vision of the album. He also changed his singing style, adding the classic growls in the end of singing fraces and adding some vibrato, witch for me wasn't so successful, because he lost that straight, heavy singing and went more towards the hard rock and country rock singing style. In Load his voice was pretty similar to Black Album but the power started living him. Reload was the beginning of losing the classic, Black Album and Load, Heatfield voice that make the band famous worldwide and more mainstream. After that his voice was changed and so did his singing style again. For me the years after Load were the weakest for him, both in studio and live. The last years it has gotten much better for some reason.
His voice has absolutely changed throughout the years in Metallica from his younger voice to his older voice in Metallica when they recorded their albums and released their Albums as well.
The best ones are from 83 to 96, reload and st anger sound weird, Reload sounds whinny and goofy and st anger is just hilariously ridiculous But it has gotten way better after lol
You can hear his voice start to transition into adult James at Load, from kill em all up to black album his voice largely stayed the same, only the quality/production of the recording on his voice changed a bit making it sound like it did change, that's what i get from listening to this. From kill em all to master of puppets theres alot of reverb added to the vocals, justice for all tones it down and sounds more direct, then black album added just a bit of reverb back. Then theres st anger which is devoid of all reverb lol
Love his wild and thrashy early days voice. Vocals suited the songs and visa versa. But I totally love the deeper, growlier, 'manlier' era...basically (to my ears) AJFA through Black and Garage Inc. I wasn't a huge fan of the music and singing style on Load/Reload. So that kind of colours my opinion of his vocals on those albums. But he obviously still had the pipes, since I really loved Garage Inc. (not just the old stuff). Anyway, one of the legends of metal no matter how you slice it, from pretty much all eras.