Whoa! Somebody found a link between Explosions In The Sky and "metal music", and that's Russian Circles' new album, "Guidance". Listen up:

https://soundcloud.com/sargent-house/sets/russian-circles-guidance

Apart from that, I received word of an album of chanting (!) by María Sabina.

The album is named "Mushroom Ceremony of the Mazatec Indians of Mexico" and is about as trippy as you're guessing. First, from her biography on Wikipedia:

María Sabina (July 22, 1894 – November 23, 1985) was a Mazatec curandera who lived her entire life in a modest dwelling in the Sierra Mazateca of southern Mexico. Her practice was based on the use of the various species of native psilocybe mushrooms, such as Psilocybe mexicana.

Also:

In 1955, the US ethnomycologist and banker R. Gordon Wasson visited María Sabina's hometown of Huautla de Jimenez, Oaxaca, and participated in a velada with her. He also brought spores of the fungus, which he identified as Psilocybe mexicana, to Paris. The fungus was cultivated in Europe and its active ingredient was duplicated as the chemical psilocybin in the laboratory by Swiss chemist Albert Hofmann in 1958.

That speaks volumes for the music. It's kind of hypnotic and there's a second voice in the background often, which I think is that of a male person, humming while María chants on. There's even dogs yapping and birds chirping at times, as it seems to be recorded through a simple cassette recorder. All of the songs are quite similar, although I don't know the language in which she's singing. It's so freakingly hypnotic. She often repeats the very same tonalities, and sings of the city San Pedro in more than one track. "San Pedro" is my fave track so far, but listen away:

Note that you can buy the album here, or even download it for free from there!