Merry Clayton's Tiny Desk concert begins with the essentials. After a brief piano intro, she begins to sing "Beautiful Scars" — the title track of her new album — in a powerful and knowing voice. That simple pairing commands attention: "I've been on the battlefield of life. / I've been through it. / But I just had to go through that to get to this." She sings in dialogue with five superb singers, all with serious gospel chops — including members of The Waters and Take 6 — and a band of seasoned pros. "Stand up and be proud of your scars," she sings. The vibe is relaxed, but purposeful.