Have you ever heard Tina Turner sing a bad version of a good song? Her complete emotional commitment to every note — have you ever heard her half-step? — requires that her material match her intensity. That, unfortunately, is far from the case on Twenty Four Seven. At sixty, Turner still sounds incredible; she’s lost remarkably little of her range and none of her power. She sweeps through the eleven generic tracks on this album with the force of a tornado whipping through a trailer park. The cornball synthetic arrangements — some misguided attempt to be contemporary? — only make matters worse. Some of the problems with Twenty Four Seven, however, are Turner’s own. Since her dramatic and much-deserved comeback with Private Dancer in 1984, she has increasingly leaned toward gleamingly clean productions and middling pop fare. She seems embarrassed by the gritty R&B that made her reputation — perhaps because much of it was recorded with her famously estranged ex-husband, the legendary Ike Turner. That aesthetic choice hasn’t hurt her career, but it has damaged her art. Twenty Four Seven is the theme-park version of this masterful performer — evocative of the real thing but ultimately harmless, which is about the last thing Tina Turner should be.