Schwarzkopf and her husband Legge loved recording, often making several different recordings of the same repertoire and in their case there was almost as much unpublised material in the vaults as they actually issued. Reasons why so much languished without a home could be manifold. It could be that at the time a slightly different emphasis was preferred, or it might simply be that a coupling could not be found, which surely must have been the case with the performance here of Mozart’s Ch’io mi scordi di te, an aria Schwarzkopf returned to in 1968 with Alfred Brendel, George Szell and the LSO and a performance that has been much admired.

However Schwrzkopf herself had misgivings about the 1968 performance. Ever an astute assesor of her own performances, she told John Steane in her retirement years,

You can hear that it’s too late, if you have a discerning ear, but it is musically good, fine, but it is not the young voice any more, and for Mozart that is not so good – it should be the voice in fuller bloom.

In 1955 the voice certainly was in full bloom and the mid 1950s might arguably be considered the high watermark of her career, vocally at least. This was when she recorded the champagne operettas, Strauss’s Ariadne and the Marschallin and Alice Ford in Karajan’s Falstaff. 1955 was also the year in which she made her US debut in San Francisco as the Marschallin.

Geza Anda, like Brendel in 1968, was a fine Mozartian and the the two artists blend and intertwine with each other deliciously. Ackermann, as so often with Schwarzkopf, is a master accompanist, shaping the music beautifully. The 1968 performance with Brendel and Szell is excellent but, if pushed, I think I would go with this one.

Thurston Dart, teacher of Christopher Hogwood and Sir John Eliot Gardiner among others, is in charge of the Bach items, and, though the instruments used are modern, the style is a million miles away from some of the over-Romanticised performances often heard around this time. Indeed Dart could be considered to be one of the pre-cursors of the HIP movement. Tempi are well chosen and Schhwarzkopf’s singing, though expressive is admirably clean and clear, her tone bright and joyful for the Wedding Cantata, but darker for Mein Herze schwimmt in Blut.

The disc also gives us the chance to hear two performances of the recit and aria Schafe können sicher weiden, the first recorded in 1957, the second the following year. To be honest there is very little difference between the two performances of the aria, but in the recitative Schwarzkopf adopts a slightly more expressive style in the later version.

Hardly anything that Schwarzkopf recorded is without interest and it is good that so much of this unpublished material has now become available, though this does mean a fair amount of duplication for Schwarzkopf completists. I’d say that this disc was worth having for the Mozart alone, but the Bach items are very welcome as well.