BBC Proms: Arditti Quartet, BBC National Orchestra of Wales, Fischer

One of the weirdest things about the Proms's "weird concerto" theme is that the concertos so far haven't been all that weird. Piano. Violin. Cello and violin. Cello, piano and violin. Pretty familiar stuff. Finally last night we got something bona fide off the wall: a concerto for string quartet from French rebel Pascal Dusapin. Was it weird enough?

To be honest, not really. But no matter. We were engaged. The work followed convention. The soloists never really departed from their showman role; the orchestra remained the backdrop. At one stage the two seem to switch places, the Ardittis taking on the chuggingly choppy figures of the orchestra (as if they were returning to Berlioz's rough-and-ready Le Corsaire Overture with which Thierry Fischer had so flamboyantly begun the evening), the orchestra melodising. These roles didn't last. Nothing that was handed to the quartet could remain mundane for long. They were soon leading the chordally hefty scrubbing in all sorts of dynamic directions (including a sort of cadenza), and on the way revealing their brilliance and Dusapin's sophistication.

It's a work that sat nicely next to the stormy rendition of Berlioz's Le Corsaire. Fischer flung his BBC National Orchestra of Wales at the Berlioz with abandon. It was a neat opener, showing off the orchestra's abilities pretty comprehensively. The Dusapin and Berlioz were segregated by a beautiful, morbid and strikingly slow Fauré Pavanne. Extremes of tempi also characterised the second-half performance of The Firebird. It's a work that crawls at such a self-admiring sort of pace, pausing only to lick its own silky fur like a pleased tabby, that I sit through it with little pleasure.

Fischer didn't do much to alleviate this self-regarding quality (I'm not sure how much one can do about this), but by the end had brought something to the piece that made it worth the effort. With the interest moving centrifugally around the orchestra, the work at least managed to show off the orchestra's form, their sharp technique and focus. Strings pitched and rolled, bowing with masterly collective tension. Principal bassoonist Amy Harman burred beguilingly. Brass blazed gloriously. And the stunning horn solo sotto voce in the final minutes was well worth the trip alone.

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