Classical Isserlis and Friends City of London Festival

If anyone ever doubted that great chamber music lives and breathes through the company it keeps, then "Steven Isserlis and Friends" will have set them right: in this company, the only discord is born of concord.

Their second concert, on Wednesday, began with Leif Ove Andsnes gazing into the mirror of Beethoven's early Piano Sonata in B flat, Op 22, and finding kinship in its temperament: a young man's fancy, an easy lyricism driven by a rebellious nature. He understood the inherent contradictions, kept the performance on the edge of its seat. The return of the slow movement's lied was a wonderful instance of freedom through formality: for just a moment, Beethoven was at one with himself - because Andsnes was at one with him.

But then there were two. Pamela Frank, violin, and Tabea Zimmerman, viola, gave us Mozart's Duo in G. And in the easy exchange of ideas and delicate dovetailing of their voices, it was as if, little by little, they were somehow assuming one another's identity. The blending and contrasting of colour was most subtly achieved, symmetry and balance could be taken on trust. Two was company indeed.

After the interval, Isserlis himself led by example, warming life into the wistful principal subject of Dvorak's lovable Piano Quintet: the first word in melody, the last word in poise. Who says great soloists cannot an ensemble make? If there was one factor above all which contributed to the success of this glorious reading, it was the very real sense that each of these players had of their own dynamic within the ensemble. Beautiful phrasings were offered and accepted, savoured and returned. To hear Andsnes take hold of Dvorak's heavenly conversion of the principal subject and render it virtually weightless, in readiness for Joshua Bell's grateful violin, was to appreciate the level at which this performance consistently charmed and delighted. It was the very essence of Czech song and dance - impassioned, uninhibited, impossibly exciting.

And just when you thought you'd heard the chamber music performance of the season... For the last concert, in Stationers' Hall on Friday, Stephen Hough slipped on to the Steinway stool to find an almost Lisztian dimension to Schubert's A minor Sonata, D 784. Parallels could be drawn here between the distillation of the first movement's second subject (a kind of "distant voices" effect) and the ghostly echoes of bittersweet salon music that pervade Elgar's Piano Quintet. Here, Frank occupied the first violin chair, her regretful portamenti seeming to shape the whole post-war melancholy of the piece, while Zimmerman's dusky viola took that achingly nostalgic slow movement melody very much to heart.

But once again, it was the corporate intensity of the performance that swept all before it, Hough underpinning climaxes of an almost Wagnerian import, leading the finale's hopeful surge towards the kind of defiant triumph that only Elgar could have imagined.

EDWARD SECKERSON