After a praiseworthy career as a mezzo-soprano, Rose Bampton made the transition to dramatic soprano, retaining much, if not all, of the plushness and warmth of her highly sympathetic voice. The step upward in 1937 came without a period of withdrawal, creating a situation that found her singing Amneris between two Aidas in the same season. Her tall, trim figure, expressive face, intelligence, and all-encompassing musicianship made her a valuable member of several opera companies, even if she was surpassed in many of her roles by certain other singers. Her Leonore in Toscanini's recording of Fidelio is a good representation of her work as a soprano, just as her luminous Wood Dove in Leopold Stokowski's live recording of Schoenberg's Gurrelieder is of her mezzo days.
Bampton lived her childhood years in Buffalo, NY, and began her music studies there. She was awarded a scholarship to the Curtis Institute where she trained for five years, working under Horatio Connell and former Metropolitan Opera soprano Quenna Mario. Initially, she trained as a coloratura soprano, but following a bout of laryngitis, underwent an examination by a throat specialist who declared her a contralto. When this opinion was confirmed by a second specialist, she undertook the study of contralto and mezzo-soprano parts.
Bampton made her debut with the New York Chautauqua Opera in 1929 as Siebel in Faust. Her appearance there led to an engagement with the Worcester Festival which, in turn, brought her a contract with the Philadelphia Opera Company where she remained for three years performing mezzo roles. Her successes in opera led to numerous offers, particularly from Stokowski who cast her in a concert performance of Boris Godunov as well as the legendary Gurrelieder performances. Bampton was welcomed by the Bethlehem Bach Festival and subsequently engaged by Toscanini for appearances with the New York Philharmonic. Other guest appearances with major orchestras came in quantity.
Meanwhile, Bampton was encouraged to seek a Metropolitan Opera audition. She was asked to return for a second hearing and thereupon offered a contract. Seized by self-doubt, she left without signing. A few weeks later, she regained her confidence and returned to put her name on the document that made her a Met artist. Her debut as Laura in La Gioconda met with decisive approval from critics. The demanding W.J. Henderson described her voice as "a rich, powerful, sensitive mezzo soprano," notable as well for remarkable evenness throughout its considerable range. Bampton sang an ever-widening number of mezzo roles over the next five years.
On May 5, 1937, Bampton introduced herself as a soprano at the Metropolitan with a Trovatore Leonora felt to be competent but lacking in temperament. Gradually, however, she achieved a greater ease in the higher reaches of the soprano register and critic Olin Downes was moved to remark that she sounded "...like a true soprano...full, free, clear in color." Bampton essayed her first Wagnerian role in Chicago, singing Sieglinde in a December 1939 production of Die Walküre. Other venues in which she sang included Covent Garden, Buenos Aires, San Francisco and, during the fall of 1950, the New York City Opera where she was heard as the Marschallin.