The great national secret is out - and it's very moving

First night: Elgar's Third Symphony

Last night's world premiere presentation of Elgar's uncompleted Third Symphony was like the public announcement of some great national secret.

Everyone knows his work and most music-lovers will have at least heard about the sketches he left at the time of his death in February 1934. Others will have been aware of the embargo Elgar's daughter Clarice placed on any attempt to, in his dying words, "tinker" with the sketches, and of the rumpus that erupted last year when it was revealed that Independent music critic and composer Anthony Payne intended to do just that.

Andrew Davis's performance with the BBC Symphony Orchestra (the same band which should have performed the piece at its scheduled premiere 64 years ago) was committed and compelling. The defiant opening marks a significant break with Elgar's symphonic past: this is big, striding music, lean, uncompromising and with a keen eye to the future, though the second idea is as tender as the parallel episode in his Second Symphony, completed over two decades before.

Payne's development of these themes culls numerous sparks from the smithy's anvil, few placed in any particular order but with four short, fully- scored passages that helped focus the rest.

There will be comparisons with Deryck Cooke's powerful "performing version" of Mahler's unfinished 10th Symphony.

But, while Cooke was an inspired Englishman abroad, Payne has, in composing stretches of the piece from scratch, intuited himself into Elgar's very soul, coaxing moments of private reverie that recall parallel passages in the first two symphonies.

The scherzo is wistful and slightly pensive; the adagio searingly intense, with a closing viola solo that carries the words "Billy, this is the end". "Billy" was the nickname of violinist WH Reed - Elgar's closest musical friend and who first put the composer's sketches into the public domain by publishing a chunk of them in the appendix to his 1936 memoir, Elgar As I Knew Him; and the meaning of the words "the end" is unequivocal, unlike the rest of the symphony, which is more mortar than bricks but still passes as creditable architecture.

Elgar's sick-room dialogues referred to the idea of having the piece "tinkered with"; the dying composer even talked of burning it - but then, like most artists, he habitually spoke on impulse. The finale was meant to be rugged and sounds it: the last musical gesture is Payne's own, a telling redeployment of an idea from Elgar's earlier Nursery Suite, maybe marking the passage from cradle to grave.

The BBCSO's performance was superb, and last night's audience grateful for the privilege of hearing it: but how will they remember the piece - as Elgar, or as Payne? Can one really think of it as both? And, since Payne's act of homage is a compelling artistic entity in its own right, does its authorship really matter anyway? I have certainly never heard a "completion" that works better, nor one that hints at what might have been with greater emotional exactitude. Judge for yourselves when last night's premiere is broadcast tonight at 7.30pm on BBC Radio 3.