The very existence of a soundtrack to a novel would seem to defy logic. Unless you’re Logic. The ambitious Maryland rapper’s fifth full-length (and first of two albums slated for this year) is indeed a companion to his just-released novel Supermarket, which is reportedly about a depressed grocery clerk who stumbles on a crime scene. Not having read the book, I can’t tell you: 1) If it’s any good, or 2) Exactly how much it does or does not have in common with this 13-track release. What I can tell you is that Supermarket (Soundtrack) has disappointingly little in common with Logic’s previous albums. The biggest difference? The artist formerly known as Bobby Hall spends more time earnestly crooning limp alt-rock and soul-pop ballads than he does rapping on this 50-minute disc. This might not be too bad, except that he’s not much of a singer. Nor is he exactly breaking new ground in traditional pop songcraft — unless you happen to be someone who’s never heard anything by Sting, Weezer, Red Hot Chili Peppers, Dave Matthews and the other artists he’s clearly and unduly influenced by here. Aside from a couple of endearingly eccentric cuts helmed by oddball Mac DeMarco, and a few much-welcome instances when Logic finally unleashes his distinctive fast-paced verbal flow, Supermarket (Soundtrack) is a disc lacking both rhyme and reason. And a disc whose earnest but deeply flawed execution can’t hold a candle to its misguided, self-indulgent ambitions. Ultimately, Logic has failed himself.