Birgit Nilsson (Telegraph)

Birgit Nilsson, who has died aged 87, was considered to be the greatest Wagnerian soprano of her day; she had a rock-solid technique and a voice of such soaring, unforced power that it was able to cut through the massed forces of a Wagnerian orchestra with ease, yet a purity of tone which enabled her to switch to the most delicate pianissimo.

She sang a wide variety of dramatic soprano roles, but her reputation was based on her mastery of some of the most punishing in the repertory – Brünnhilde, in Wagner’s Ring cycle, which she sang on her debut at Covent Garden in 1957 and Isolde in Wagner’s Tristan und Isolde, which she sang at her Met debut in 1959, an event that confimed her as a successor to Kirsten Flagstad, the Norwegian soprano who had dominated the Wagner repertory before the war.

She excelled also as Elektra in Richard Strauss’s opera of that name and as the fire-and-ice heroine of Puccini’s Turandot.

Birgit Nilsson’s extraordinary vocal power and breath control enabled her to hold on to flawless high notes for almost unnatural lengths of time, a facility which involved her in frequent battles of climactic high Cs with the almost equally dazzling tenor Franco Corelli.

A story is told of how, on one occasion during the second act of Turandot, Corelli was so enraged at being unable to sustain his top note for as long as hers that he took his revenge by biting her on the neck during their love scene in the third act.

Birgit Nilsson is said to have pulled out of the next performance, explaining: “I have rabies.”