At her best, J. Lo combines and energizes familiar dance-pop sounds to make music worth getting lost in (in 1999, “Waiting for Tonight”; in 2011, “On the Floor”). On her eighth album, however, she just sounds lost. Beyond summer-anthem contender “I Luh Ya Papi,” Lopez supplements flat production from names like RoccStar with forgettable verses from rappers like T.I., claims street cred but offers nothing to show for it and awkwardly seeks cool in third-rate Diplo beats and New York’s underground vogue scene. Later, she indulges in puns as shameless as “Expertease” and “bootyful” – though, to be fair, that last one comes from guest star Pitbull.