I try to be really careful about classifications when I start talking about subgenres of heavy metal music. This is because there's always some smartass nearby itching to correct me -- usually because I need to be corrected. When it's stuff I don't spend a ton of time listening to, I can get particularly facile in my categorizations. For example, when I hear guttural, horrorshow vocals or screams like someone who's just been clubbed in the nards and likes it, I generally think, 'oh, death metal.'
Such vocals are an acquired taste, to put it lightly, and that's fine, because it's an aesthetic choice. By this I mean that I can say with some certainty that these guys don't go home after a show and speak to their mothers in that tone of voice. It's cultivated. They are speaking to a very large and rabidly devoted community of music fans who are all in -- for them, the vocals are an indispensable part of the music experience.
I've never been dismissive of death metal because more often than not the music behind the vocals is intensely interesting. Nowhere will you find as many folks who actually have studied music theory and even composition than in this little corner of the rock and roll world. Ultimately, even if you can't get used to the singing (I generally can), the musicianship more than makes up for it.
So I'm probably not being as careful as I should be when I apply that term -- death metal -- to a very exciting band out of Raleigh called Acrasia. I throw that term out there because most of the time, vocalist Michael Rumple's singing sounds like the bellows of hell. Again, it's an aesthetic choice -- at several points during their self-titled full length, Rumple actually sings, revealing a powerful and far-ranging voice.
But is it death metal when you listen to the band winding through these complex and beautifully played songs and think that you could just as easily envision them putting out their next album on an old prog label like Relativity or the now-defunct E.G. Records as you could see them signing to Metal Blade or The End? I don't want to create an impression by saying they play art rock that their music is not apocalyptic and bonecrunching. It most certainly is both of those things. Check out album opener "Pulse", which will put any such concern to rest.
Here's the second song, "Waves Within", which will remind you of some of your favorite Isis tunes, albeit with much showier guitar work from Zach Dresher and Devin Janus (never a bad thing), and an aggressive foundation laid by bassist Blake Privette and drummer Alex Finn. Again, you can hear the band's progressive leanings burrowing in and out of the song. It's prog like Mastodon, but it's also prog like early 70s King Crimson.
The album is exceptionally strong from front to back, with superb production by Jesse Clark. Take a look at their bandcamp page and listen to "Contextual Relevance", which features a fascinatingly unforced saxophone part right in the middle of a cyclone of noise.
Then buy the whole danged album. It's cheap, it's great, and they deserve it.