Arguably the most adventurous female jazz singer of all time, Betty Carter was an idiosyncratic stylist and a restless improviser who pushed the limits of melody and harmony as much as any bebop horn player. The husky-voiced Carter was capable of radical, off-the-cuff reworkings of whatever she sang, abruptly changing tempos and dynamics, or rearranging the lyrics into distinctive, off-the-beat rhythmic patterns. She could solo for 20 minutes, scat at lightning speed, or drive home an emotion with wordless, bluesy moans and sighs. She wasn't quite avant-garde, but she was defi...