The curiously named Diabolicus are a chamber (or café) ensemble of up to 17 players including piano, harmonium, guitar and mandolin. The arrangements were originally made for a Viennese musical society and were prepared for a small ensemble for reasons of economics, although of course Wagner’s Siegfried Idyll is heard here as originally played for Cosima by 13 instruments, and delightfully intimate it sounds. The playing is of the highest quality, rhythms are crisp, tuning is excellent. The accompanying photograph shows members of the group playing against an elegant café background but they have been heard also at the Opéra Comique and other venues. A most enjoyable programme then, with the Emperor Waltz standing out alongside Denza’s Funiculì-Funiculà and Busoni’s Berceuse. The latter is an extraordinary nine-and-a-half minute piece, brief, intense, darkly atmospheric and written on one dynamic level. It is certainly haunting and described by the composer as “a lullaby sung to a deceased mother by a man leaning over his mother’s coffin, staving off grief with the image of a candle”. It makes a curious finale.