Sigur Ros, the acclaimed experimental Icelandic band, on Monday announced a North American tour of small theater shows with stripped-down instrumentation to test material for a new album.

Sigur Ros said it would be the first time since 2002 that the band would play unreleased material on the road, part of its bid to write music for its upcoming eighth album.

"In keeping with the scale of the venues, the group will be performing without the string and brass sections that have been characteristic of recent performances, opting instead to focus on the core unit of the band itself," it said in a statement.

Sigur Ros won wide critical praise starting in the late 1990s through its highly experimental and often melancholy works, which evoke nature with a blend of classical and rock elements.

Hallmarks of the band include a bowed guitar, long minimalist build-ups, frontman Jonsi's falsetto voice and scat lyrics in a language dubbed "Hopelandic."

The band will start the North American tour on September 19 in Vancouver and mostly play small theaters over the following month, although it will also perform at New York's Radio City Music Hall.

Accustomed to playing arenas, Sigur Ros said the North American tour would mark the first time the band will play without an opening act, instead performing two unique sets with an intermission.

Sigur Ros has already announced a summer tour of Europe but mostly large festivals, starting with Primavera Sound in Barcelona.

Sigur Ros has not released an album since 2013's "Kveikur," although Jonsi has been active on side projects.