Amihai Grosz, principal viola player of the Berlin Philharmonic, gets a well-deserved spotlight here in two superb and expressive concertos from the 20th century. William Walton’s Viola Concerto was composed in 1929 as the English composer was entangled in matters of the heart. (Walton subsequently revised the orchestration in 1962 to improve its clarity.) Simon Rattle, noted for his strong empathy with Walton’s colourful and jazzy style, is the ideal conductor here, while Grosz digs deep in the opening “Andante comodo”. By sympathetically bringing out its moments of sweet lyricism, Grosz heightens the impact of the short melancholy cadenza he plays towards the end of the opening movement. In the virtuosic second movement (“Vivo, e motto preciso”), Grosz complements the Berlin Phil's lithe, tensile performance with neat and precise playing. And in the concerto’s final orchestral climax, Rattle and players reveal more than usual of the music’s suppressed anguish, making sense of its bittersweet conclusion. Martinů’s Rhapsody-Concerto, composed in 1952 while the exiled Czech composer was living in New York, is in a similarly wistful vein. Under conductor Matthias Pintscher, the Berlin Phil captures the troubling undertones that lie beneath its largely pastoral character. Grosz performs with great empathy, playing the second movement’s folk-like melody (symbolising Martinů’s distant homeland) with a moving simplicity.