Schumann and Brett Dean are the two composers featured most prominently at Cheltenham this year. They mesh nicely, because Dean is also a world-class viola player (a former member of the Berlin Philharmonic), and during his festival residency has taken part in chamber music performances, as well as conducting and playing in his own works. At the core of the Schumann bicentenary tribute were three concerts curated by cellist Steven Isserlis, the first of them, concentrating on chamber music, the most intriguing. As well as a thrillingly high-octane account of the Piano Quintet, with Dean and Isserlis joined by pianist Dénes Várjon and violinists Katharine Gowers and Magnus Johnston, and a nicely judged Fantasiestücke Op. 88 for piano trio, from Johnston and his cellist brother Guy with Izabella Simon as pianist, there were two real rarities. Bilder aus Osten, a suite of intermezzos for piano duet, isn't particularly distinguished, but the Andante and Variations Op. 46 most certainly is, an extraordinary work for two piano, two cellos and horn.

An early evening concert directly juxtaposed Dean and Schumann. Before Schumann's G minor Piano Trio, played just a bit too assertively by Alexandra Wood, Robin Michael and Huw Watkins, Philippa Davies had given a remarkable performance of Dean's feisty Demons for solo flute, and the composer conducted his own Winter Songs, settings of EE Cummings completed 10 years ago for the unusual combination of tenor (Thomas Hobbs) and wind quintet (London Wind). Dean creates webs of deliquescent, wintry sounds, through which the singer threads the atomised texts, syllable by syllable; it's fragile and transient, and finally delicately elusive.