Isn't even mastered.
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I've heard it. It sounds very open and organic. They eschewed the usual loudness maximizing shit, stereo enhancers, and just went with a more raw sound (honestly, the individual tracks were mixed damn near perfect anyway).
Interesting. Not saying loud and enhanced albums sound bad - I think KsE's TEoH is both loud, wide and sounds great! Of course, the newest Metallica lbum sounded like total dogshit, from a recording perspective (I liked the songs OK, for the most part).
It makes sense, really. With the way recording technology has gone, it's a lot easier to get consistency during tracking/mixing, and the original purpose of mastering was partly for consistency, but mostly for the actual cutting of the master for vinyl pressing and getting the most out of that medium. Hell, that's why so many early CD releases sound so terrible, the tracks were mastered for vinyl (mid heavy, not much lows or highs because they make it hard for the needle to track the groove, and it's all made up for on the playback side) and never re-mastered for CD.