Vocals have always been a part of jazz music. Louis Armstrong revolutionized music with his horn and natural singing style. Billie Holiday and Frank Sinatra used standard songs as a means for personal expression and how they phrased their lines influenced others well past the Swing era. The lush voices of Billy Eckstine and his protege Sarah Vaughan worked in the Bop idiom that they helped create. While Ella Fitzgerald could front a full string orchestra with an amazingly pure voice, she could also scat better than even Mel Torme, who epitomized the 1950s Cool West Coast scene with his sophisticated, light swing. Betty Carter took singing further out by abandoning the narrative of lyrics and influencing arty Post-Boppers.