Lugubrious and grumpy they are not. In the wrong hands, though, Brahms’s cello sonatas could emerge that way because the lines are susceptible to clogging during strenuous moments, of which there are many. One of them occurs between 8'33" and 8'40" in the first movement of the First where the cello is at the bottom of its compass and both instruments are required to play fortissimo. Sonia Wieder-Atherton and Imogen Cooper – intelligently balanced – maintain the power without muddying the passage. At the opposite end, they hold the tension for the very soft, near nostalgic beauty of the E major coda, as they do for the many bars of pianissimo writing in the last movement of the Second Sonata. Nor is romantic breadth and passion, found everywhere, overlooked. Not since Mstislav Rostropovich and Rudolf Serkin have these works been interpreted with such compulsive acuity; but even Wieder-Atherton and Cooper cannot make the arrangement of the violin sonata sound persuasive.

The Bach transcriptions are persuasive. They enhance a disc whose artistic magnificence is not devalued by some changes in volume level or the presence of often intrusive breathing noises from Wieder-Atherton. She is a touch dispassionate in the aria from Cantata No 33 but seems perfectly happy multi-tracking both the soprano and alto parts in the aria from No 78. But Cooper steals this particular show in a meltingly moving re-creation of the Sonatina from Cantata No 106 that ought to be played first and last