Such is the popularity of The London Bridge Trio (Tamsin Waley-Cohen, Kate Gould and Daniel Tong) and their assorted guests that last Friday evening’s concert took place not in Winchester’s restricted Discovery Centre but in the more spacious Theatre Royal. It’s clear that audience figures for this weekend-long festival have markedly increased since its launch in 2008 and, judging by Friday’s full house, the local appetite for high quality chamber music has soared. Not a note of Beethoven or Haydn was heard at this year’s festival; the focus instead turned on Mozart and Schubert with an exploration too of Czech composers Dvořák, Janáček and Martinů.

Friday evening was Viennese Night and began with the chamber version (i.e. no oboes or horns) for strings and piano of Mozart’s Piano Concerto in A major, K414. Supporting Daniel Tong (piano) were Matthew Truscott, Clara Biss (violins), Scott Dickinson (viola), Philip Higham (cello) and Laurene Durantel (bass) – all invited players and in varied stages of their careers, some already distinguished. There was much to admire in the first movement with well-judged tempi and effortless sensitivity to dynamics with the main themes clearly outlined. It took a while to get used to the light, “semi-skimmed” sound of the strings which conveyed delicate control rather than raw excitement. Possibly their style was influenced in some measure by the leader, Matthew Truscott, who divides his time between period instrument and modern performance.

It took a while also to adjust to the venue’s acoustic which did little to enhance the impressive-looking Fazioli piano, all brightness seemingly leached from its middle register. Despite its parched-sounding timbre Tong engaged with Mozart’s playfulness in the opening Allegro and charmed us with his eloquent phrasing in the Andante. Had the players brought a greater sense of fun to the concluding Rondeau (piano and bass were notable exceptions) the thrill-factor would not have been quite so absent. This concerto was, after all, written not long after Mozart’s marriage in 1782 and during one of the happiest and most successful periods of his life.

From Mozart’s short-lived bliss, the programme moved forward nearly 40 years to a period of similar contentment experienced by Schubert in the summer of 1819 when he wrote his Piano Quintet in A major “The Trout”. For this Waley-Cohen led the four-part string ensemble and from the start of the main theme her sweet-toned Stradivarius made an immediate and vivid impression. Each player here was wonderfully assured and brought to the ensemble flawless intonation and musicianship, but the underlying characteristic of Schubert's chamber music – written for friends and played for friends – was often missing. It was as if everyone was a reluctant party-goer. Interplay with one another and visible communication is everything. That said, there were many memorable moments, the pin drop dynamics towards the end of the slow movement were breathtaking and Schubert’s variations (what incredible resourcefulness!) could have been twice as long so beautifully were they executed, especially the exhilarating fourth variation. By the last movement players seemed to be more relaxed and the music’s unbuttoned quality emerged.

After the interval, and fast forward five years in Schubert’s life there followed his hour-long Octet in F major. Of the eight players three – Tamsin Waley-Cohen, Matthew Truscott and Scott Dickinson – faced clarinettist Robert Plane, horn-player Sue Dent and bassoonist Julie Price, while Kate Gould and Laurene Durantel occupied centre stage. With this horseshoe positioning the players responded superbly to the way Schubert so generously distributes his melodic material, and in this performance each player knew exactly when to hog the limelight and when to slip back into the shadows. And what shadows! Few composers can combine the light and the dark so comprehensively as here, a work in a major key that often feels minor. Even the extended opening chord at the start seems to traverse the full emotional spectrum from joy to sorrow.

Plane particularly found expressive opportunity in the clarinet’s theme in the Adagio, and if the rustic element in the third movement could have been a touch coarser, the variations were magnificent, Durantel driving the ensemble forward like a bass player in a jazz combo. The sense of regret that colours the Minuet was finely caught, especially in the eerie waltz of the central Trio. It was in the concluding movement (begun with fearsome tremolandi) that we heard the full extent of this ensemble’s virtuosity not least in Waley-Cohen’s rapid arpeggio figuration dispatched with stunning precision. Performances like this don’t get much better but it would have been a bonus to have seen more obvious enjoyment on stage.