SUMMER ALBUM ROUNDUP : In Brief

** 1/2 Alan Jackson, “Don’t Rock the Jukebox,� MCA. With three, maybe four, hits out of 10 attempts on his sophomore outing, Jackson’s performance would be a stunning success on the baseball field. On the diamond of country music, however, he’s still just a promising rookie--likable, but mostly unexceptional. Best exception: the witty Ernest Tubb redux “Walking the Floor Over Me.�

Albums are rated on a scale of one star (poor) to five (a classic).