East L.A.'s greatest-ever band has so far spent the 21st century backing away from the formal and textural experimentation that marked the work the group did in the 1990s. In 2002, Good Morning Aztlán winningly showcased the band's roots -- a hard, Latin-keyed rock and soul with plenty of swing -- but felt a little dry for the lack of interplanetary keyboard slime. For The Ride, Los Lobos drafted musical contributions from a troupe of impressively varied guest stars, perhaps in an attempt to reintroduce some of that mystery into their sound. Often they succeed: Mexican art-rockers Café Tacuba charge opener "La Venganza de los Pelados" with a nimble rhythmic thrust; Tom Waits adds deranged babble to "Kitate," the barely coherent sound of a carnival melting into mush; Rubén Blades gives "Ya Se Va" a humid open-air throb. Yet even the more conventional stuff here feels fresher than 12th albums tend to; check the submerged menace that keeps threatening to surface in "Is This All There Is?" or how off-the-cuff Mavis Staples's vocal sounds in the organ-drenched "Someday." In a long medley of Lobos' "Wicked Rain" and Bobby Womack's "Across 110th Street," the band (along with Womack) pushes past bar-band tedium into old-soul beauty. And they actually make a medley work.