When soul singer Jerry Lawson left his a cappella group the Persuasions in 2003, after having performed with them since 1966, it looked like he would become just another obscure name in the annals of musical history. Although Lawson and his fellow street corner vocalists had sung on acclaimed albums of their own and with Joni Mitchell and Stevie Wonder, they seemed past their prime. When Lawson joined vocal outfit Talk of the Town in 2004, he proved he still had a voice and arranging skills to be reckoned with. In 2010, the group enjoyed a long run on the a cappella competition program The Sing-Off and Lawson dueted with show judge and former Pussycat Doll Nicole Scherzinger. Last year, Lawson did something completely new: Working with formerly D.C.-based alt-country musician/producer Eric Brace, he recorded Just a Mortal Man, his first solo album, backed by musicians. Sounding relaxed on some tracks (Paul Simon’s “Peace Like a River”), world weary on others (Brace’s “Time and Water”), and always powerful yet in control, Lawson turns R&B and country numbers into vehicles for his own fervently emoted, heartfelt expression. Jerry Lawson performs at 8 p.m. and 10 p.m. at Blues Alley, 1073 Wisconsin Ave. NW. $20. (202) 337-4141. bluesalley.com.