The album has a score of 66 out of 100 from Metacritic, indicating "generally favorable reviews" [REF].
The A.V. Club gave the album a C and called the Mars Volta "a band that excels when its sing-alongs double as freak-outs; on Octahedron, they've largely ditched the chaos in lieu of an admirable, albeit unsatisfying, experiment in being quiet."[REF]