Soprano sfogato

Soprano sfogato ("Vented" soprano) is a term which, in the art of singing, designates a contralto or mezzo-soprano who is capable—by sheer industry or natural talent—of extending their upper range and being able to encompass the coloratura soprano tessitura. An upwardly extended "natural" soprano is sometimes called soprano assoluto.

In the early 19th century as well as in the baroque and classical periods, distinctions between voices were not based so much on the range as in the tessitura and color of the voice. There were two main groups: soprano and alto. Their range was often blurred, relying more on tessitura to cast different roles in opera. In Italian bel canto, the soprano did not have extremely high notes actually written (often just to B5 or high C♭) and it was not until the "nightingale" type of sopranos such as Jenny Lind, Fanny Persiani, Adelina Patti and her imitators that ending the cabalettas in a climactic high E or E♭ became traditional as it was in the French grand opera which became so popular when Rossini moved to Paris. Singers however did ornament higher than high C but in a light and fast way as it was done still in the classical and baroque periods. Virtuosity was shown by quick-silver agility, changes in register and tessitura, perfect control of dynamics and tonal coloration, not by whistle-like high notes.

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