I hardly imagined that Testament would be able to trump its Wagnerian ace as regards the Keilberth Ring (3/06, 9/06, 1/07, 2/07) but here they are a few months later presenting us for the first time with the concert in 1950 when Flagstad gave the premiere of Strauss’s Four Last Songs, followed by some truly unforgettable Wagner; in my book, it’s the latter that makes the CD so exciting.

As Michael Tanner opines in an interesting booklet-note, these two formidable artists had several collaborations in these Wagnerian excerpts, but caught live in very reasonable sound they produce performances that lift one out of one’s seat. Furtwängler is in incandescent form in the Tristan excerpts, and even more so in the Dawn and Rhine Journey from Act 1 of Götterdämmerung. The music whizzes along with the most virtuoso contributions possible from the recently formed Philharmonia, the horns, headed by Dennis and Aubrey Brain, very much to the fore. Flagstad then sings the Immolation with quite wonderful freshness and conviction, and this at the end of a longish programme. The results are to invoke thetingle factor. It is worth mentioning that the pair had just been giving Ring cycles at La Scala and seem entirely at one in their readings.

The Tristan Prelude and Liebestod offer a similar frisson. Has the Prelude ever sounded so impassioned and urgent as here? Did Flagstad, in her numerous recordings of the Liebestod, ever convey so much tragic passion? I think not, and she is in much better voice than in the complete 1952 set.

The performance of the Strauss, previously available on the grey market, is now heard in improved sound; but Flagstad, for all the richness of her singing, gives a fairly generalised interpretation compared with many that were to follow, and the conductor was never the greatest of Straussians. Still, as a historic document this is an important issue. The whole disc, carefully remastered, is a treasure.