Not so long ago, in 1992, Sir Colin Davis conducted the London Symphony Orchestra through a Sibelius symphony cycle at the Barbican which has passed into the realms of "Were you there?" mythology. And it proved as important for Davis himself as for anyone else, restoring his status in this country after years of semi-exile overseas and fixing him in the minds of British audiences as something more than the major conductor whose presence, or absence, we had come to take for granted. Suddenly, he was a great conductor. And that discovery earned him his current Principal's job with the LSO.

In the ordinary course of things, we wouldn't have expected another Sibelius Cycle from Davis for at least a decade. But the memory of those 1992 performances has been revived by an equally impressive cycle on disc - for BMG - which has just reached its conclusion, and won a Gramophone Award in the process. By common consent, Davis is now the leading Sibelius interpreter around. And the LSO has accordingly decided to do the symphonies again - starting last Sunday with Nos 1 & 2, in what will be a chronological run.

The first thing to say about this initial instalment is that it more than justified the decision to repeat the cycle so quickly. The performances were stunning; the orchestra on top form; and the hall was, as it were, on heat.

The second thing is that it shed some light on how we choose to hear the Sibelius symphonies a century after they first appeared. On disc there's a wealth of possibilities, with established cycles from Rattle and the CBSO, Ashkenazy and the Philharmonia, Bernstein and the New York Philharmonic, Maazel and the Vienna Philharmonic. Davis's new recorded cycle with the LSO is in fact his second: he made one in the 1970s with the Boston Symphony. And there's another, surprisingly fine cycle in the making from the Lahti Symphony Orchestra under Osmo Vanska. The glut recalls how things must have been early this century, when British audiences made a cultus of Sibelius as the symphonist of modern times.

But we approach Sibelius more critically now. One persisting debate concerns the degree to which he was a self-made phenomenon from a country with virtually no musical tradition, rather than a by-product of Wagner and Tchaikovsky. As a Finnish nationalist, Sibelius was naturally hostile to suggestions that he owed much to a Russian; and he publicly dismissed the "circus" antics of Tchaikovskyan Romanticism. And yet, to hear the 1st and 2nd Symphonies is to hear a certain debt. And one of the strengths of Colin Davis is the way he holds that debt in a judicious balance with the tougher, stripped-of-sentiment pursuit of form that marks Sibelius as his own man in these early scores. You feel the forging of new sound- worlds out of old. But there's a radiant majesty as well that warms the chill of what would otherwise be pure abstraction. And while the textures are lean rather than luscious, the attack is strong - in grand, unfussed, rather patrician terms. I doubt if any other prominent Sibelian has so sure a grasp of these old/new, warm/chill equations. It outclasses Rattle, Ashkenazy, everybody. And from Sunday's opening concert it was clear that this new cycle will repeat - perhaps exceed - the triumph of the last.

There were no so such expectations for the Royal Opera's revival of Otello, in the new and unpromising circumstances of the Royal Albert Hall. With limited stage facilities it could only reconstruct the bare bones of Elijah Moshinsky's handsome production; and the make-do nature of it all was summed up by the way the grand Corinthian columns of the original set now rest on crude, mock-marble plinths that look like cladding from a Billericay bungalow. There's no front curtain, so the set-changes are exposed. But then there's not much set to change. And in the interests of economy it's largely done by extras: men in armour touchingly turned furniture-removers.

For all this, however, it's a somehow decent show. Vladimir Bogachov isn't the most sophisticated or expressive tenor, but he has Italianate resonance, and by the end of Act 4 on Monday he had made more of the title role than seemed possible at the start of Act I. His Desdemona was Daniela Dessi, making an impressive Royal Opera debut: rich and full, if vocally a touch too heavy for the role. And the ever-reliable (if conspicuously Russian) Sergei Leiferkus substitutes for an indisposed Alexandru Agache as Iago, which is no misfortune. The acoustic of the Albert Hall tends to emphasise the wrong things: moving bodies and offstage effects rather than the voices you might prefer to hear. But with resort to some discreet amplification (about 15 per cent of the singing is, as they say, "enhanced"), you get by. Honestly.

One of the most civilised fixtures in the British music calendar is the Bath Mozartfest; and it was no less so this year for being sponsored by Ushers the brewers, who marked the occasion with a special Mozartfest beer. I caught two of this year's concerts, both featuring oriental pianists. One was Melvyn Tan playing Mozart's Piano Concerto K466 on a modern grand oddly positioned with its tail to the audience and the player lost in the surrounding London Mozart Players, and I can't say I enjoyed it. As with all Tan's recent efforts to transfer to "new" Steinways the technique he developed on "old" fortepianos, it felt forced and contrived, like someone working overtime on expressivity. With fortepianos, no doubt, you have to make that extra effort. With Steinways you don't.

A far happier experience was Mitsuko Uchida making joyful and spontaneous- sounding work of Mozart's Piano Concerto K413 in a chamber version with the Brentano Quartet of New York. I'm not sure that K413 gains much from being done by just five players, but Mozart authorised the reduction himself. And there was no questioning the depth of relationship Uchida enjoys with this remarkable quartet. I'd never heard the Brentano before - this was their British debut - but I knew of their reputation. And the agile, wiry intelligence of their playing, in a constant state of alert, was every bit as good as promised. They followed with as momentous a performance of Beethoven's Op 130 quartet as I've ever heard live - complete with the Grosse Fuge finale, so vast an undertaking that it's often played as a separate piece. But here it felt proportionally right, within a general scale of playing that was passionate, uninhibited and spell-binding.

Less spell-binding, though, was Wednesday's Golden Wedding Royal Gala at the RFH, which must have been nice for Queen but did little for the cause of anything beyond the shoulder-pad and big-hair industries, whose products interlocked like barricades across the top-price (pounds 400) seats. A celebration of love and marriage in Shakespeare's and the music of composers who set him, it staggered lifelessly through various mismatches of voice to repertoire, on a stage which had been transformed into something like a working-men's club redesigned by Terence Conran. Gilded twigs stood fashionably on the organ console; alternating lights smothered the LPO in blue and purple; smoke-clouds drifted through the auditorium. If I could be sure Tony Blair's plans for the monarchy would put an end to this nonsense, he'd get my vote in perpetuity. But I've an awful feeling it's exactly what he has in mind.