From the explosive maximalism of “Merriweather Post Pavilion” to the mind-bending one-of-a-kind acoustic sounds on “Sung Tongs,” Animal Collective has adeptly explored a wide spectrum of psychedelic sounds across its several studio projects. The band’s latest album, “Isn’t It Now?,” skirts closer to the reggae-influenced sounds of last year’s “Time Skiffs” than the freak folk.