Modern recordings of Arnold Bax’s great Viola Sonata are thin on the ground and so it is a joy to welcome this full-blooded newcomer by the Jamaican-American virtuoso Jordan Bak, who is perfectly partnered by pianist Richard Uttley. Composed in 1920 for Lionel Tertis, the sonata comes at the first peak of Bax’s compositional career: hard on the heels of his orchestral masterpiece Tintagel and immediately before the epic First Symphony. It also belongs to the full flood of his affair with the pianist Harriet Cohen, and the contrasted passion, anguish and deep contentment of this relationship sing through in the pages of a now-neglected masterpiece, which Bak embraces with complete commitment and unfailing charisma. He is blessed with a soaring upper register plus impeccable intonation and irresistibly conveys all the lyrical ardour of the music as well as its vigorous dancing rasp.

This intricately programmed recital is the latest in Delphian’s valuable partnership with YCAT, the Young Classical Artists Trust, and is captured in close but vividly atmospheric sound in Edinburgh’s Greyfriars Kirk. It opens bracingly with the unaccompanied Chant by Jonathan Harvey, in which a singing cantus firmus in the depths underpins visceral higher harmonics in a dazzling display of technique. The theme of song and singing runs throughout the programme and is embodied in Vaughan Williams’s ravishing early Romance. Bright Sheng imbues a beautiful Chinese folk song with radiance although Augusta Read Thomas’s aspiration to find a wordless song for an unspoken poem proves both elusive and inconclusive. Written for Tertis’s successor William Primrose in 1950, Britten’s Lachrymae is a set of haunting variations in search of a Dowland song, and when this magically does arrive it emerges with the strange recognition but deep mystery of sheer genius – a quality eloquently matched by Bak’s commanding range of sonorities and interpretative insight: a wonderful album.