Next year the Vienna-based Quatuor Mosaïques will celebrate their 20th anniversary. When they first came together they had the quartet literature almost to themselves as far as period performance was concerned; and even now chamber music is far less comprehensively explored by historically aware ensembles than the orchestral, choral and operatic repertoires.

The Mosaïques began their collective career with Haydn and Mozart but, like the period-instrument movement in general, they have gone on steadily to colonise more and more of the 19th century too. Now they have reached Brahms and his C minor quartet, Op 51 no 1, was the final work in this Wigmore programme. It was also by a long way the least satisfactory performance of the three they gave, and one in which problems of intonation regularly soured the textures.

In both Haydn's E flat quartet Op 20 no 1 and the sixth and last of Beethoven's Op 18 set, in E flat, though, such difficulties seemed far away. Paring down vibrato as the Mosaïques habitually do puts a premium on accurate tuning, in any case, but everything in these two works was transparent and pure, with deftly sprung rhythms and neatly turned phrases, even if there was not always enough sense of cumulative weight about the way in which movements ended.

In the Brahms, however, that same reluctance to take the music by the scruff of its neck and impose a personality and purpose upon it was more of a problem. The C minor quartet may be thematically coherent, with each new idea a logical consequence of what has gone before, but it still needs to be interpreted, to be given direction; the Mosaïques let the music lead them, especially in the outer movements, rather than taking control themselves, and it was there too that the tuning difficulties made themselves a bit too obvious.