Credit: Ashanti: James Hicks/UHI/London Features

Ashanti made her entrée into R&B the new-fashioned way: by lending coy hooks to jagged-edged rappers. She doesn’t stray too far from formula on Ashanti, her debut album — duetting with Ja Rule on ”Leaving,” using an El DeBarge sample made famous by Biggie Smalls on ”Foolish.” But she should aim higher. Her voice is supple and pretty but rarely rises above a whisper, making it a background instrument even when it’s Ashanti’s turn to shine.