Three CDs. The Nightingale of the Andes, the voice of birds and earthquakes, the Peruvian soprano Yma Sumac was the most singular and vivacious of recording artists. Her other-worldly vocal gymnastics, a freakish four octave range delivered with sensitivity and power, were without peer in her day and still sound like nothing on Earth. Her natural versatility was such that the Spanish composer Manuel de Falla advised her to sing spontaneously and to avoid formal music teaching at all costs. The Quintessence spans the halcyon days of the 1950s, featuring the six albums which, taken together, have permanently crystallised the myth of Yma Sumac. From the torrid landscape of sensual exoticism that is the Voice of the Xtabay – her genre-defining, best-selling collaboration with Les Baxter – through the hot mambos and languid perfumed psychedelia which underpins her subsequent North American productions, created by her conductor, composer and (then) husband,