Devendra Banhart’s brain is probably one of the strangest places on earth. It’s populated by dancing crabs, pedophiles, really hairy mountaineers, peace pipes, sleeping butterflies and teeth. Its landscapes and climate zones include rainforest, desert, frosty woods, Venezuelan slum and China. He sings about all these things with a warbling voice, a guitar and, more recently, a full band. His music resists genre definitions: It’s been called New Folk, Psych Folk and Freak Folk. But none of these really say anything. It’s just uniquely him.

Devendra Banhart’s most recent album, “Smokey Rolls Down Thunder Canyon,” shows this unclassifiable, often brilliant, musician faltering. Experimentation with genres has always been a part of his musical agenda, and historically it’s only served him well: Incorporating elements from different cultures and styles has diversified and strengthened his sound. This experimentation has grown from his earlier albums to reach a pinnacle in “Cripple Crow,” his previous venture, where he appropriated Latin, rock, bluegrass and other styles, skillfully blending them and making them his own. But here, on “Smokey,” this eclectic genre-hopping has shown its ugly side, becoming scattered, random, forced and often boring.

This is especially disappointing because he gathered a full band for this album, and they’ve named themselves Spiritual Boner. One might hope that this communality would allow for more intricate and organic instrumentation, but most of the tracks sound fairly standard. Some of the songs are well arranged (most notably “Seahorse,” “So Long Old Bean” and “Carmencita”), and some even have a real ensemble power. The worst parts, though, happen when Banhart tries and fails to imitate genres. His nods to particular musical styles are too obvious, too forced: He accomplishes the mimicry through recognizable and predictable instrumentations.

The most depressing moments of the album are when he alters his beautiful voice to fit into one of his genres. Case in point: in “Shabop Shalom,” Banhart sings an ode to a Rabbi’s daughter he is in love with, in a pseudo doo-wop style. He puts on the smooth, buttery sounds of a’ 50s lounge singer, and the result is truly, truly unfortunate.

But even if the music sometimes disappoints, the album art is a nice compensation. An unfortunate side effect of the widespread preference for downloading music online is that the liner notes and accompanying album artwork are cast aside. iTunes makes up for this by sometimes including “Digital Booklets,” but the effect is really not the same as holding the thing in your hand. For this album especially, buying the tracks from iTunes seems like sacrilege: half of the joy of owning the CD is the thick (as in, 50-plus pages) book that comes with it. It’s full of the signature DB art that decorated most of his previous albums. Here, a Hispanic-looking man with a long mustache and sombrero gazes sadly from the page, replicated many times with various props and ostensibly having crazy hallucinations. Here also are lyrics written in what appears to be Banhart’s own script, and in the back we see some fun photos of Banhart and his crew.

Judging by these photographs, Banhart seems to enjoy playing dress up, and his music reflects this inclination, as he tries out different genres for size. He sometimes succeeds, but when he fails, he fails miserably.

At the album’s close, after finally slogging through the last few tracks, the overwhelming feeling is one of disappointment, even betrayal. There are a few shreds of the beauty that marked his previous work, but these are rare and often buried in sonic muck. There are no really wonderful tracks, nothing to make this album worthy of multiple listenings. Hopefully, for Banhart’s sake, this just marks a slip in what has been an otherwise strong career. Pray that the next album will be better!