Recorded between 1999's Times of Grace and 2001's A Sun that Never Sets, Neurosis' Sovereign EP functioned almost as much as a document as a new piece of media. By the point Sovereign was released, the group was just completing its transition to the modern form of the band. Their hardcore thrashing was long in the past, and even their doom metal grind, while present, was being overshadowed by dark, heavy ambient textures and sheer volume.

Still, while Neurosis was branching into virgin territory, they remained attached to their past. The EP's opener, "Prayer" functions very much like Black Sabbath's signature tune, where vocalists Steve Von Till and Scott Kelly begin reflecting on themselves and addressing a nameless, ominous entity hanging before them. But, where Black Sabbath would break down into crushing blues, Neurosis moves father away from soulful territory into booming, clanging, chords that continually build in scale, until finally, instead of crashing upon their own weight, hang suspended before vanishing.

As with later Neurosis works, Sovereign leans heavy on the group's experimental side, dropping in extended audio clips, distanced tribal drumming, and meshes acoustic guitars next to electric, each at the same volume. While later Neurosis works would sometimes get bogged down by these elements, almost making them diversions, because the EP is compact (for a Neurosis album, that is) they pull the group from the glut of drone/doom bands into a singular heaviness without being cheesy or too self-aware.

This 2011 reissue features a previously unreleased track from the same session, and remastered sound. "Misgiven" keeps in line with the rest of the release, featuring a distorted, clomping bassline, before devolving into pure feedback, proving a fitting freakout endpiece to an EP that was formerly fairly listener-friendly. The new sound increases the album volume, but luckily, not to the point where range or quality of sound is lost.

With a rumored 2012 release in the works, it is likely that Neurosis will continue getting father and father out there to the reaches of blackness. Sovereign is unique in that its arguably the last piece where there was still a few glimmers of light left in the band's sound.