The words have failed them all. Since by the time you've read this far you've already read words that are intended to be touchstones but which do nothing but make it easier to not hear what should be all about hearing: their music.
So let's dispense with "stoner" and "doom" and while "metal" is a good catch-all even that does what SLEEP does an injustice. What SLEEP does and has been doing since 1990. Since San Jose. Since vocalist and bassist Al Cisneros hinted darkly at his next act after Asbestosdeath. Make something that was like something you had never heard/felt before even if you had heard/felt it before. Like wind or the yawning subsonic expanse of an earthquake: something undeniably large.
And like ragas, the songs were not just songs but movements and the movements trended toward the eternal. Almost time-wise too with songs that lasted as long as some entire records, which is as long as it needs to be to get short-sighted labels to drop you. And beyond time, the weight was equally significant. Heavy, sublime and not even a little bit ridiculous and whether or not these were influenced by the sacramental consumption of weed really misses the point.
While there may have been a few like them before them, there were none like them really and certainly none of after them. And so in 2009 when they were reborn with Cisneros who'd been reframing the world with the band OM, Matt Pike doing double duty with this and his HIGH ON FIRE, and the estimable Jason Roeder doing the same with NEUROSIS, SLEEP did what it had done and what it had left to do. Largely and without pause, make music in tune with The Ages.
Best to be enjoyed? Live and living. See, hear, feel, do it. Well, beyond just music and well into the experiential joy of pure being. SLEEP. Undoubtedly.