The Pfitzner impresses by its command of form: its tonal structures and contrapuntal textures are worthy of Brahms, the main sign of immaturity being the lack of continuity between the intensely serious first two movements and the burlesque character of the scherzo and finale. In the scherzo, more a piano solo than a duo piece, Silke Avenhaus grasps her opportunities with panache and style; elsewhere, the playing is notable for the close, easy co-operation between the two artists. By 1920 Weill had adopted an intensely chromatic idiom, firmly anchored, however, by a relatively straightforward rhythmic and metrical structure. The sonata is introspective in mood, yet with some highly imaginative lighter touches. Avenhaus and Viersen find considerable variety of colour, seizing on the finale’s grotesque character before enjoying its tranquil, impressionistic coda, like a calm sunset after a stormy day.

The performance of Barber’s Sonata makes an interesting contrast with the magnificent 1979 live recording by Charles Curtis and Earl Wild, especially in the first movement. Here, Curtis and Wild pace themselves more broadly, emphasising the eloquent gestures, whereas Viersen and Avenhaus concentrate on a passionate forward motion. Both approaches seem valid to me, and, indeed, I can thoroughly recommend all the playing on this disc – assured, intelligent and deeply felt.