In 1957, she described her early voice as: "The timbre was dark, almost black—when I think of it, I think of thick molasses", and in 1968 she added, "They say I was not a true soprano, I was rather toward a mezzo".
V roku 1957 popisuje svoj raný hlas: "farba zvuku bola tmavá, takmer čierna – keď o ňom premýšľam, predstavím si hustú melasu," a v roku 1968 dodala "hovoria, že som nebola pravý soprán, skôr to smerovalo k mezzo."