The Shahams, brother and sister, make a formidable team. It’s obvious throughout that they’re entirely comfortable playing together, effortlessly accommodating any freedoms in timing and matching each other’s tone and dynamics. The six sonatas Mozart published in Paris in 1778 make an excellent programme, though to fit onto a single CD it’s necessary to miss out quite a few repeats – the only really unfortunate omissions occur in the variation movement of K305.

I can’t, however, really recommend the performances. Gil and Orli Shaham take Mozart’s dynamic marks very literally: in particular, they feel the need to sustain the forte passages at a relentlessly high level, sometimes even giving a brutal air to the music, and forgetting that stylish 18th-century phrasing demands a continual differentiation between strong and weak notes. There are some places where the Shahams’ block dynamics seem suitable – as in the dramatic minor-key Allegro of K304 and the brilliant D major first movement of K306 – but much of the time the subtlety of Mozart’s rhetoric is lost. Another recurrent problem is the lack of a steady tempo. Mozart, more than any of his contemporaries, possessed the art of combining many different ideas and characters within a single tempo; the wonderful effect of this disappears if, as in the first movement of K302, each new motif signals a change of speed, destroying Mozart’s carefully crafted unity and balance.

If “Mozart in Paris” is a disappointment, this certainly isn’t true of the Prokofiev. Granted that the Shahams’ insistence on clearly separating each phrase sometimes results in a loss of momentum (in the opening Moderato of the Op 94 Sonata, for instance), these still emerge as brilliant, highly expressive performances. The particularly wide dynamic range – of the recording as well as of the playing – here works decisively to the music’s advantage. And, especially in the Cinq Mélodies, we hear those subtle shades of expression that are so often missing in the Mozart. Both players have clearly entered right into Prokofiev’s distinctive idiom. They show the divergent natures of the two sonatas exceptionally vividly – Op 80 sombre and concentrated, Op 94 full of ebullient fantasy.