To date Knappertsbusch has been represented in Lohengrin only sporadically on disc. This new discovery still provides a late throw of the dice for the sort of ‘heavy’ interpretation of earlier Wagner that had already been abandoned at the Festspielhaus. A Siegfried (Hopf) and a Brünnhilde (Bjoner) take leading roles, and there is a Götterdämmerung-like weight in the fanfares and processional music.

Unhappily, however, the basic sound of this preservation is poor – an unresonant and tubby brass timbre and relatively overloud timpani. Voices placed upstage centre – Lohengrin on first arrival and Ortrud interrupting the Act 2 procession – sound as if they’re especially amplified or treated, perhaps due to unfortunate microphone placing. The accidents in ensemble, especially in the tricky layering of Act 1’s ‘Seht! Seht! Welch’ ein seltsam Wunder’, make this feel finally like that unrehearsed Knappertsbusch performance of legend.

There are rewards: the rare chance of hearing the Norwegian Ingrid Bjoner on disc complete in a major role. Her ‘big’ career in Wagner, Strauss and Verdi coincided unfortunately with that of Birgit Nilsson, although Bjoner, mostly denied Bayreuth, was able to make Munich her home base for new productions. If you compare her with today’s Elsas of choice (for example, Annette Dasch), you may find her over-regal and matronly but Bjoner is clear and good in the role’s sorrow and frustration, especially moving in Act 3 when she can’t call her husband by name.

After a bumpy start to the evening, Knappertsbusch, like Kempe, establishes a firm grip on the through-line of the often disparate Act 2 and does not stint on the melodramatic excitements of Act 3. Hopf has genuinely musical power but rarely finds outside ‘In fernem Land’ the emotion and colour of Melchior. Nöcker gives us Telramund as pure baddie rather than a case study in psychological confusion. Varnay is (just) starting to sound her age but remains an unfailingly stylish and spooky reader of Ortrud’s character. King and Herald are strong, straight and no-nonsense.

There are a number of cheaper historic Lohengrins ranging from Melchior with Fritz Busch or Leinsdorf at the Met via the early New Bayreuth experiments of Keilberth, von Matačic´ and Sawallisch to the also recently unearthed ‘new’ mid-’60s Karl Böhm. I would not rank this uneven release above any of those as a performance to live with; but if you love this opera and are interested in the development of performing Wagner, you need to hear this set.