Since we are here mainly concerned with the vocal aspect of the case, let us for the moment disregard the considerable difference between Solti and Karajan as Wagnerian interpreters, and consider the casting. The first thing we notice, in scanning the casts of the two sets, is that neither of them attempts to achieve the consistency in casting the principal roles that Wagner himself took for granted - for he would surely have been amazed and horrified by the practice, known even at modern Bayreuth, of employing a different Siegfried for each of the last two parts of the tetralogy. Admittedly, there is rather more excuse for inconsistencies of this sort in a gramophone recording of the entire cycle spread over seven years (Decca) or even four (DG); but the customer is likely to feel that, if he must in any case change his Wotan or Brünnhilde in passing from one opera to the next, there can be no very serious objection to his making the larger switch from Decca to DG, or vice versa, in the course of the cycle.

Both companies have a Wotan (and also a Mime) who appears in Das Rheingold only; thereafter, Decca pursues the more consistent path, sticking to their great trump card, Birgit Nilsson, for all three Brünnhildes, and to the no longer young but still satisfying Wolfgang Windgassen for both Siegfrieds. In the DG cycle Karajan drops Régine Crespin (wisely, I can't help feeling) after Die Walküre, entrusting the two later Brünnhildes to the more fresh-voiced but inexperienced Helga Dernesch, and similarly jumps from Jess Thomas to another newcomer, Helge Brilioth, for the more mature Siegfried of Götterdämmerung.

What lies behind these arbitrary-seeming changes of course? Partly, no doubt, Karajan's feeling that, as sole conductor and producer of the Salzburg cycle, he himself is the real mainspring of the whole enterprise, with a deeply pondered conception of the work and enough rehearsal time at his disposal to ensure that any young and reasonably gifted singer can be duly moulded into the required pattern. But also the harsh fact that there are barely enough first-rate Wagner singers around anywhere today to provide a single fully adequate and experienced Ring cast, let alone two. Imagine two rival Rings to have been recorded in the inter-war period, and the difference becomes plain. Whichever company had to do without Frida Leider could have had Elisabeth Ohms or Gertrud Kappel - and, later on, the young Flagstad; Bockelmann or Rode would have made fine and interesting alternatives to Schorr; while, even though Melchior's position as the world's first Heldentenor was unassailable, we should not have been too badly off with Franz Völker or Gotthelf Pistor or Walter Widdop. The notion of entrusting anyone of these enormously taxing roles to a newcomer could hardly have arisen.

Karajan's decision to cast his leading roles with young, light, essentially lyrical voices was bound to cause most difficulty in the dark, heavy, heroic score of Götterdämmerung. True, Brünnhilde and Siegfried are only a day older than they were in the previous opera; but that is not at all the impression we receive as the sinister and tragic action unfolds. Brünnhilde, in particular, must develop from the radiant youthful rapture of the Siegfried duet and 'Zu neuer Taten' through the tragic horror and outrage of the second act to the mysterious all-comprehending wisdom of the final scene. With all her talents, Dernesch cannot achieve this: she hasn't the necessary weight and ringing authority of tone. She suggests well enough the wronged and pitiful woman, but not the outraged fury (a figure from Greek tragedy, almost) of the great denunciations of Act 2. She is at her best in the long scene with Waltraute (once more, as in the Decca set, the magnificent Christa Ludwig): for example, in the very intimate, dream-like tone she adopts for the passage in the lower register of the voice ('Welch' banger Träume Maren') that immediately follows Waltraute's Narration; but she conveys little of the grandeur and final exultation of the Immolation Scene.

Similarly, Brilioth excels in the lively, quick, unemphatic dialogue style (often more appropriate than the traditional heavyweight manner) which he brings to his early scenes with the Gibichung family; but there is too little solidity, too little weight in his bright, clear tones for the more heroic aspects of the role. Karl Ridderbusch offers something most unusual, a highly civilised, bel canto Hagen! His singing provides much pleasure, and rings out finely in the scene with the vassals; but he is relatively weak in the lower register and conveys little of the dark malevolence of the character - least of all in that wonderful passage when he is left alone on guard after the departure of Siegfried and Gunther for Brünnhilde's rock. Janowitz, whom I had expected to excel as Gutrune, is not well suited by the music; and Stewart, in rough voice, is no match for the Gunther of Fischer-Dieskau in the Decca set.

Notwithstanding these drawbacks, the set as a whole is enormously enjoyable, especially for the refinement and beauty of the Berlin Philharmonic's playing; Karajan's reading, though not deficient in power or impulse, has the merit of reminding us how much sheer lyrical beauty there is in this black and complex score. Indeed, I was often bowled over (for instance, in the exquisite realisation of the Norns' Scene) by the new recording; and it was only on returning to the more dynamic, more strongly cast and more richly recorded Solti version that I was forced to admit its general superiority.

If the choice between the two Götterdämmerungs is fairly straightforward, it is by no means so, however, when we consider the cycle as a whole. Each series of albums has qualities, and each has faults, which the other lacks. For example, all the understanding and profundity of Hans Hotter's Wotan cannot, for me, hide the fact that much of his singing in Siegfried, and still more in Die Walküre, is distressingly insecure and off pitch; the far from godlike but much more steady and efficient performance of Thomas Stewart is a strong argument in favour of the DG sets of these two operas. But on the other side of the ledger we have the glorious Brünnhilde of Nilsson, who far outclasses Crespin, especially at the beginning and end of her Walküre role. Each collector must balance these and many other considerations for himself. I see that in the case of Die Walküre I ended by casting my vote in favour of Karajan and DG; and I should probably make a similar decision in Das Rheingold, where Karajan's lyrical handling is especially appropriate and Fischer-Dieskau offers an uncommonly fascinating Wotan. Siegfried is more problematical; only in Götterdämmerung does the choice (this time for Decca) become more clear-cut. 

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