Six years after the dissolution of R&B boy-band B2K, 25-year-old singer Omarion describes his third solo album, “Ollusion,” as proof that he’s all grown up. But the set comes off more like a bid for street cred than maturation. Lyrics full of hip-hop bravado over dirty, distortion-heavy beats are found on “Hoodie,” “Code Red” and “I Get It In” (featuring rapper Gucci Mane). “You can find me in your city, steezed out with a hoodie on/I go so hard,” Omarion snarls on “Hoodie.” Meanwhile, the track “Last Night (Kinkos)” stalls under the weight of a strained metaphor (“When I put you on the copy machine, body printed out just right”). And the lustful “Wet” somehow manages to sound unsexy. But when Omarion reaches for the high notes and sticks to nuance on the aching ballad “Speedin’ ” and the teasing “Sweet Hangover,” he shines like a seasoned star.