Sigur Ros may have dubbed themselves a "slow-motion rock" band, but anyone who carries this notion into their new album will be shocked by the opening "Gobbledigook." The song is a swirl of sounds, with multiple layers of vocalizations and bright guitar strumming. It is an unexpected and refreshing turn for Sigur Ros, a band that is used to slower compositions but nonetheless sounds comfortable working with both slow and fast tempos throughout Med sud i eyrum vid spilum endalaust while still employing their greatest strength: creating the gorgeous sonorities that make their albums so breathtaking.

Unsurprisingly, the album's most awe-inspiring numbers are the longest ones, where the band is free to develop its sound gradually. "Festival" is a beautiful piece, with angelic vocals in the first half and understated electric guitar, a quickening drumbeat and churchly strings in the second half. But the album's shorter pieces are just as strong, especially ditties such as "Illgresi," which features double-channel fingerpicking and moving string harmonies. The upside of the album occasionally becomes its weakness, however: The unwaveringly tranquil instrumentation of the more passive numbers is often moving, but not all of it is completely inspired.

Nonetheless, with its diversity and consistency, Med sud i eyrum vid spilum endalaust feels fully-realized and ranks among the best of the band's catalogue. The album is at once energetic and tame, classical and experimental: It demonstrates both the different and familiar faces of the Icelandic band. And while each of Sigur Ros' albums is intriguing, none of them is as immediately accessible while being so delicately structured. This album may not only be one of the band's most masterful; it could very well be among the most masterful of this year.

-Rajesh Srinivasan