On paper the Introduction and Allegro looks conventional enough but it springs to life in this interpretation by Michael Collins and Michael McHale as they give full measure to the appassionato marking, moving the music onwards and upwards. In Undine they catch the sprite’s capricious nature, revelling in her mischief in and out of the waves as she is propelled along by the piano’s rippling accompaniment. The Intermezzo and Andante, each composed with alternate fast-slow-fast sections, are played in disarming fashion before the athletic finale, where the reprise of the più lento theme is touching.

Brahms called Mühlfeld ‘a master of his beautiful instrument’, an epithet that could be extended to Collins who, with McHale, offers joyous performances of these lyrical but unsurprisingly cogent works. Their tempi in all the movements of both sonatas are well chosen. Details to relish include the wind-down of the coda to the first movement of the First Sonata that is both sustained and expressive, as marked by Brahms, with feeling for the flow of the uninterrupted melody in the Andante and the lilt of the Ländler in the Allegretto. Their dynamic shaping of the phrases in the brilliant Vivace brings it to a thrilling conclusion. The Second Sonata’s opening movement is truly amabile, the stormier paragraphs of the succeeding movements executed with aplomb. This is a most desirable issue, with a recording that balances the two instruments perfectly.