We are still tracking the data, but the following is our best guess (so far) about a New Orleans concert program excerpted here. It should be noted that several factors preclude commercial release of the material: the details of the program could not be verified; the sound quality of the tapes is not is great as one might hope; there are flaws in timing both between orchestra and soloist and within the orchestra; and the opening bars of the encore are missing. However, I think you will agree that the performance is extraordinary and that Nilsson's voice is captured here about as well as on any recording.
I can't tell you a date, although it was prior to 1973. The conductor would have been Werner Torkanowsky.
Dich teure Halle Tannhäuser
Liebestod Tristan und Isolde
Du bist der Lenz Walküre
Brünnhilde's Immolation Götterdämmerung
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