She was one of the three vocal miracles Tullio Serafin had witnessed during his career, singers had only the highest regard for her: the two Rosas (Raisa and Ponselle) were a „mutual adoration society“, “When discussing singers you must first set aside Rosa Ponselle and Enrico Caruso. Then you may begin.” (Geraldine Farrar), „She was the greatest of us all.“ (Maria Callas) and Walter Legge praised the beauty of her voice: „Vintage port and double-cream richness paired with a noble line.“
There certainly is no denying that she started right at the top. Without ever having appeared on any operatic stage before she made her debut at the age of only 21 (given that her birth date 1897 is correct) in the demanding role of Leonora in „La Forza del Destino“ opposite no one less than Enrico Caruso at the Metropolitan opera. It was almost exclusively an American career, the only exceptions being three seasons at Covent Garden and a production of „La Vestale“ at the Maggio Musicale Fiorentino in 1933. After barely 20 years she bid farewell to the operatic stage, her voice still being in considerably good shape – although it had darkened considerably and settled into a lower placement.
At her best she encountered hardly any vocal difficulties. She had an exceptionally wonderful legato, an evenness of the registers, an unusual flexibility for such a large and powerful voice and she possessed a fine trill. Her obsession with top notes seemed to be more a psychological than really a vocal problem. I might agree, however, speaking of Ponselle as an interpreter, with a remark a critic made on the occasion of her debut in 1918: „The note of monotony in the tone colour that occasionally intruded must be avoided: nuance, nuance, nuance.“