Amid the post-war rebuilding of Dresden, singing Fidelio was like performing a church service, says soprano Christel Goltz in the bonus DVD in this lavishly packaged Vol 2 of Profil’s Semperoper Edition. Though makeshift Fidelios were heard as early as 1945 at a spa hotel in the Dresden suburbs, this stark, expressionist 1948 production opened the Staatstheater with an excellent cast that still reflected the cultivated values of pre-war Germany but had an extra post-war subtext that gave Beethoven’s parable of political oppression an extraordinary level of musical engagement. Goltz, for one, uses some extravagant pre-war portamento with an electrifying effect that doesn’t feel dated – and is rendered with astoundingly modern, warm, clear sound quality. Missing, though, are the opening ensemble, Leonore’s great ‘Abscheulicher’ aria and the Prisoner’s Chorus; apparently the tape was snipped so that parts of the opera could be broadcast individually, and not all of them survived.

The overture is vintage Joseph Keilberth with a lean, bristling sonority, the slow sections attenuated with an intensely lyrical line and climaxes that are long in the building but land perfectly on target. The booklet-notes say the performance isn’t 100 per cent identified; Keilberth was considered politically suspect at that time, wasn’t mentioned during the broadcast, and thus the Overture was archived without his name attached. My ears, though, haven’t the slightest doubt.

Vocally, the principal singers tend to be Wagnerites, which means that Goltz’s Leonore, for all her dramatic commitment, isn’t as tidy as we’re now used to, while Bernd Aldenhoff’s stentorian Florestan uses the language with authority but not nuance. The hugely effective Josef Herrmann had a great way of making a soft landing on a note that comes to a sharp peak – in keeping with the character. Commenting on the rest of the cast is hard when so much is missing. However, the 178-page booklet is stuffed with photos, logs and all sorts of memorabilia. The bonus DVD has interviews with many who were there, including soprano Lisa Otto. Though everything is in German without subtitles, newsreel footage of the finale and Keilberth filmed from the pit are plentiful compensation.