My two favorite recordings of this opera both come from 1952, and are both remarkable yet so utterly different: the studio Furtwängler and the live Karajan. Furtwängler may very well be the most significant figure in the history of Wagner interpretation, and here he delivers a spacious, deeply compelling interpretation that is still to my mind unmatched in its tragic intensity and in it's ability to submerge the listener into this hypnotic world. Neither of the leads were young, and they don't sound it, but they both have great voices, and under the inspired guidance of Furtwängler they surpass themselves. This is especially true of Suthaus, whose Tristan has a depth and intensity, together with accuracy in pitch and rhythm, which make him unique in recordings of this demanding role. Flagstad sounds mature, but also inward with the role, and manages the whole range of Isolde's feelings in Act I, which has a hardly bearable tension in this recording. I also can't think of a better warning to the lovers by Brangäne than the one from Blanche Thebom and Furtwängler here, becoming a miracle of sensuous translucency.
On the Karajan recording from Bayreuth, Martha Mödl simply is Isolde, and with her the character is brought to life, complete and complex, more than in any other account on record. Vinay is a noble and tormented Tristan and suffers movingly in Act III. And Hans Hotter starts off shaky as Kurwenal, but soon becomes the role's most moving and convincing exponent. Karajan conducts with fire, volatility, and an abandon that makes this completely unlike the kind of performances he was giving decades later. There are plenty of inaccuracies, one or two near-disasters, and quite a lot of stage noise to be sure. But this is an indispensable set.
I also really like the Carlos Kleiber studio effort which is passionate, almost feverish. My own slightly idiosyncratic view is that the recording under Reginald Goodall is also one of the finest, as far as conception of the work is concerned, and up to a point even in execution. Tempi are slow, but never feel it. Goodall shapes the acts with all the certainty that Furtwängler achieves, and he has in Linda Esther Gray a most moving Isolde. John Mitchinson is a stolid but reliable Tristan. However the point is with conducting on this scale, the love duet, which lasts for more than forty-five minutes, is shaped in one overpowering arch, leading to a climax the likes of which I haven't heard elsewhere -- this despite the deficiencies of the Welsh National Opera orchestra.
