WIKIPEDIA:

“ Octahedron is the fifth full-length studio album by American progressive rock band The Mars Volta, released on June 23, 2009. The album was released by Warner Bros. Records in North America and Mercury Records worldwide. It debuted at #12 on the Billboard 200 Album chart with sales of 29,980 in its first week of release.
Regarding the release, vocalist Cedric Bixler-Zavala states that the band "wanted to make the opposite of all the records we've done. All along we've threatened people that we'd make a pop record, and now we have."

Development
Omar Rodríguez-López was working on Octahedron at the same time as The Bedlam in Goliath, as is typical for Rodriguez to be working on two or three projects simultaneously. Yet as Bedlam turned into a "nightmare of a record to make" Rodriguez was unable to sustain both projects and devoted his attention on Bedlam.
Rodriguez had discussed the band's next album (then untitled) as early as January 2008, the month that The Bedlam in Goliath was released, claiming "I consider it to be our acoustic album." Cedric Bixler-Zavala has also spoken of the album as "acoustic" and "mellow," yet stated: "We know how people can [......] ”

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