The Mars Volta Octahedron Released June 23

After releasing last year’s thrashing, Ouija-inspired The Bedlam in Goliath, singer Cedric Bixler-Zavala vowed The Mars Volta’s next album would be its long-awaited acoustic record. One expected the antithesis of the epic spazzed-out psych rock that has characterized the band’s past four studio endeavors. It instead iterates the hyphenated duo’s vision in a more mellow and easily digestible form.

Octahedron is unquestionably the most concise in a series of kaleidoscopic concept albums. At just under an hour, this motley collection of eight incohesive but independently striking songs (many saturated with Omar Rodriguez-Lopez’s usual screeching riffs) doesn’t exactly fulfill Bixler-Zavala’s promise, perhaps to the elation of long-time fans.

With tracks like “Teflon,” rife with flanged-out guitar slides and forward-driving percussive pounding, the band appropriately counterpoints the shadowy gypsy lull of ballads like “Since We’ve Been Wrong.” Octahedron succeeds in taking devoted listeners on the space-quest they’re looking for, while placating those who get easily impatient with the band’s typical prolonged guitar breakdowns, replacing them with melodic plucking and airy soundscapes — a style that the band doesn’t pull off quite as smoothly. As it turns out, The Mars Volta’s brilliance is more evident in up-tempo numbers than slow serenades, which consequently seem over-abundant in Octahedron.

Dirty Projectors Bitte Orca Released June 9

When Dirty Projectors orchestrator Dave Longstreth attempted to cover the entirety of Black Flag’s Damaged from a listening distance of one and a half decades, the result was one of 2007’s most buzzed-about albums, Rise Above, in which the band coined a notably unique sound, pairing acoustic guitar arpeggios with choral oohs and aahs before transitioning into discordant electric clamor under Longstreth’s endearing falsetto. Bitte Orca contains much of the same chamber-choir vocal harmony, but features the addition of dreamy synth ambience and more complex electronic beats. Singer Amber Coffman’s breathy soprano, usually limited to backing accompaniment, translates surprisingly well into a lead. Her staccato chanting in the jangly pop tune “Stillness is the Move” — which pushes the album to its height with the introduction of gently falling violins — and sultry drawl in “Two Doves,” a seventies-inspired folk song, are pleasing but too reminiscent of other quirky chanteuses to be remarkable. The vocal trio still dazzles the most with Longstreth at the helm and the ladies doo-wopping behind, like in the twangy “No Intention.” Bitte Orca is indeed the band’s most accessible record to date, but seems to suffer for it; the DPs’ eccentric charm doesn’t often get a proper showcase in these nine tracks, which make for a fine melodic pop record, but don’t really do the group justice.