As in his first concert this season with the London Symphony Orchestra on Sunday, Adams the composer-conductor moved last night from the natural phenomena of an older master to his own illuminated chronicle of man-made unease. City Noir, his latest orchestral symphony in all but name, bears his trademark knit of rhythms both bludgeoning and capricious with sinuous melodic nocturnes: the mixture rather as before, but with a fresh twist of LA jazz. You'd think the marriage of harmony and invention would free up his conducting of other men's music. Oddly, though, that remained doggedly beat-bound, to be saved at the last minute by Jeremy Denk's astounding sense of fantasy in Stravinsky's Concerto for Piano and Wind.As in his first concert this season with the London Symphony Orchestra on Sunday, Adams the composer-conductor moved last night from the natural phenomena of an older master to his own illuminated chronicle of man-made unease. City Noir, his latest orchestral symphony in all but name, bears his trademark knit of rhythms both bludgeoning and capricious with sinuous melodic nocturnes: the mixture rather as before, but with a fresh twist of LA jazz. You'd think the marriage of harmony and invention would free up his conducting of other men's music. Oddly, though, that remained doggedly beat-bound, to be saved at the last minute by Jeremy Denk's astounding sense of fantasy in Stravinsky's Concerto for Piano and Wind.

As one who came to know the B minor Mass singing in a clogged, 150-strong choir, I welcomed the authentic-movement rush in the 1980s to  whittle it down to What Bach Might Have Wanted (if, indeed, he had lived to hear his ideal religious compendium performed in its entirety). For a while, it shrivelled to anorexic dimensions in the shape of Joshua Rifkin's one-voice-per-choral-line hypothesis.

What would you imagine the composer John Adams might choose to conduct – apart, that is, from a little something he himself made earlier? Well, the first of two London Symphony Orchestra concerts this week brought no big surprises: Sibelius’ Sixth Symphony was in essence a little like returning to his minimalist roots – a bunch of insistent melodic cells and dancing ostinati. Flanking it, as if to reassert that everything Adams writes is essentially operatic, was orchestral music born of opera: Adams’ own Doctor Atomic Symphony and the “Four Sea Interludes” from Britten’s Peter Grimes. Adams, the conductor, had his work cut out.

Mastery was always going to be the overriding virtue of Mariss Jansons's latest appearance; his many visits to London with one or other of his continental superbands guarantee nothing less. But would it, to paraphrase Callas's immortal masterclass question, favour expression or fireworks? The options remain open, for Jansons at least, even in as severe a work as Shostakovich's Tenth Symphony, unquestioned masterpiece but also a tour staple. Jansons steered his cultured, mobile Bavarian players neatly, not dispassionately but a little weightlessly through every gear change of the titanic first movement. It was a Sarah Waters novel, an elegantly negotiated page-turner, rather than a Hilary Mantel epic written in blood. Then, with the liberating horn cry of the pivotal third movement, expression conquered all and never let go.Mastery was always going to be the overriding virtue of Mariss Jansons's latest appearance; his many visits to London with one or other of his continental superbands guarantee nothing less. But would it, to paraphrase Callas's immortal masterclass question, favour expression or fireworks? The options remain open, for Jansons at least, even in as severe a work as Shostakovich's Tenth Symphony, unquestioned masterpiece but also a tour staple. Jansons steered his cultured, mobile Bavarian players neatly, not dispassionately but a little weightlessly through every gear change of the titanic first movement. It was a Sarah Waters novel, an elegantly negotiated page-turner, rather than a Hilary Mantel epic written in blood. Then, with the liberating horn cry of the pivotal third movement, expression conquered all and never let go.

If Beethoven’s Third Symphony Eroica was the seismic upheaval, not just for Beethoven but for the entire symphonic movement, then the Second Symphony was most certainly the pre-shock. And we can be precise about the moment that Beethoven blows the Haydn model right out of the water and glimpses the far horizon of his brave new world: it’s the extended coda of the first movement where a devious harmonic shift sets collision course for the rip-roaring climax in which the trumpets turn wilful dissonance into exultancy.