London Symphony Orchestra / Riccardo Chailly Barbican Centre, London
Funeral rites, funeral music, a funeral pyre. Immolation, sublimation - and redemption; through love, through death. Weighty days for Riccardo Chailly and the London Symphony Orchestra. It's not often that super-heroes Wagner and Mahler come face to face (or is that back to back?) at the twilight's last gleaming. In real time, this most compelling of reunions amounted to a mere hour-and-a-quarter's music. But when you're talking composers with a mind to change the world, then you're talking two lifetimes of substance.

In the opening movement of Mahler's Second Symphony, the hero of his First (no prizes for guessing who that is), is borne unceremoniously to the grave. Totenfeier ("Funeral Rites") is the first draft of that first movement. The remainder of the symphony, the so-called Resurrection, came later, much later. Indeed, for a time Mahler came to view this torsoless head as an independent symphonic entity. To hear it performed as such (and we rarely do) is an unsettling experience. Quite apart from the acute sense of "unfinished business" (all of the questions, none of the answers), such differences as do exist between this version and his later revision are incredibly revealing. There are the changes in instrumentation, the way Mahler audibly becomes Mahler, extending the range of timbres at both extremes of the sound spectrum, from the shrill, demented E-flat clarinets and extra piccolo on top, to the string basses and contra-bassoon on the bottom of the underworld. Without them, the sound of this earlier version is flatter, less astringent. Then again - and this is yet more pertinent - there is a sense in which the music (which is substantially the same) is not yet fully-formed. At the start of the development, in a passage sounding for all the world like an act of self-sabotage, are several pages (later discarded) of disorientating limbo. For anyone familiar with the movement as it appears in the symphony, these are moments of almost perverse modernity, frozen moments stripped bare of all their expressive particulars, cryptic clues in search of a final solution. In this powerful performance Chailly was uncompromising in his exactitude, crashing the emotional gear- changes, hitting the precipitous transitions with little or no regard for anyone's safety. Least of all his own. Just so.

Which might explain why the convulsive outrage of Siegfried's funeral music proved less than seismic in the second half of the programme. Those mighty displacements can wrong-foot even the great and good of orchestras - including the London Symphony. But this final segment of Gotterdammerung Act 3 was as much an excuse to array the talents of Britain's latest international Wagnerian heroine, Jane Eaglen. And she rose to it. It's a fabulous voice, big and lustrous wherever it takes you. And its ability to express anger and compassion within the compass of a single phrase, equally to beguile and to hector, demonstrate just how well its resources are being nursed. This Brunnhilde sounded young and fresh, yet could despatch those ravens to ramparts of Valhalla with thrilling authority. Alright, so the words never quite conveyed their full dramatic import, so true transcendency is not yet within her grasp. But Eaglen really sings this music, seeking out the "bel canto" in it, welcoming the great "redemption of love" motif with a glorious open-heartedness. And that's a good place from which to grow.

Chailly, too, grew through these final pages, mindful, no doubt, that Bruckner's Eighth Symphony was already high on the horizon. Friday's performance was mightily impressive in one respect above all others: foresight. Chailly will take a passage like the trio of the scherzo - a real garden-of-the- world affair replete with fragrant harps - and he'll savour its effulgency. But not at the expense of the broader context. His way with this music is eminently "vocal" in that even Bruckner's most eternal phrases are sung through with a very real sense of where the melody and harmony are leading us. Not for Chailly the monolithic, mausoleum school of Bruckner conducting, but rather something well-earthed and vibrant. The LSO responded with what sounded like deep and abiding gratitude, powering even the problematic finale with renewed urgency all the way to the coda's triumphant entry into Valhalla. And hadn't we been there before?