I f this live recording from Ensemble Modern and HK Gruber represents an eclectic snapshot of musical Germany between 1920 and 1933, it’s also a perfect example of the kind of thing the Nazis couldn’t abide. “Too modern, too jazzy, too Jewish,” they cried. No surprise then that all four composers ultimately wound up in the United States. Dancing on a Volcano: Ensemble Modern Premiered in 1922, Hindemith’s Kammermusik No 1 was condemned by one critic as having “a lewdness and frivolity only possible for a very special kind of composer”. Gruber embraces its neo-classical spikiness and jazz-age energy in a performance of almost cartoonish glee. Korngold, as epitomised by his 1920 music for Shakespeare’s Much Ado About Nothing, is Hindemith’s polar opposite. In a lively reading, Gruber leavens the composer’s Viennese neo-Romanticism with a pinch of acerbic wit. Schoenberg’s Accompaniment to a Cinematographic Scene, which premiered under Klemperer in 1930, is eight minutes of existential angst.…