Montserrat Caballe "Vissi d'arte", Tosca. Opera fans refer to her "floated" pianissimo — a sustained soft note in the upper register. It's essential to every soprano's vocal armory. Caballé set a new standard for it — her pianissimo was angelic. It didn't just enchant your ear — it stopped your heart. Her technique was so unobtrusive that she hardly seemed to draw breath at all. She'd gently lift her voice onto a high note and let it float serenely, like a sailboat on a quiet lake.