It’s more than a decade since Steven Isserlis’s RCA disc of Schumann, that time around coupling the Concerto with his Opp 70, 73 and 102. It was widely acclaimed at the time, but this new recording reveals a still deeper empathy with the composer. Isserlis has long been a stalwart champion of Schumann, through his advocacy of not only the often-maligned Concerto but also the chamber works. For this disc he has had to beg, borrow and steal but the results absolutely justify the means.

In the wrong hands, a work such as the Fantasiestücke, Op 73 (which Isserlis plays in its earliest incarnation), can sound a touch seasick, with too much swelling through every phrase, and a loss of the overall shape as a result (even artists of the calibre of Natalia Gutman and Martha Argerich can fall into this trap). What repeatedly struck me here, however, was how well Isserlis paces everything. Some of his tempi are quite spacious but this gives the music a wonderfully considered and luxuriant aspect; the results never ever sound contrived. That’s partly to do with Isserlis’s sound (extravagantly he uses not one but two Strads on this recording), which has a very focused centre to it, but also his utterly innate relationship with pianist Dénes Várjon. Perhaps the most ravishing item on the disc is the poignant Abendlied, arranged by Joachim from its piano duet form but then further borrowed by Isserlis, playing it down an octave. In his hands it’s as moving a wordless Lied as anything you could imagine.

The substantial work here, though, is the Third Violin Sonata. Two of its movements – the Intermezzo and finale – originated in the multi-composer “FAE” Sonata written for Joachim (for which Brahms famously wrote the Scherzo). Schumann later added two more movements to form his last large-scale work. It decisively refutes the theory that he had – metaphorically and literally – lost the plot by this stage. While it certainly doesn’t conform to standard 19th-century sonata form (though nor do a number of other great sonatas, not least those of Chopin and Alkan), in Isserlis’s hands it’s a work of compelling power, whether in the terrifying scherzo sections of the second movement or the dreamy Intermezzo, a muchneeded point of repose in a work of great tumult.

The disc ends with the Fünf Stücke im Volkston, and finds Schumann in a more folky idiom. Too often these pieces can sound like an awkward amalgam of styles, but Isserlis again is utterly inside them, revealing Schumann’s innovation even at this late stage, from the edginess of the first, via the tender, Brahmsian second one to the spirited fifth piece, where Mendelssohn collides with Bartók. For all that Isserlis has made many wonderful recordings, not least his seminal Bach Suites, I think this might just be his finest yet, with warmly detailed sound (Isserlis’s usual dream team of Simon Eadon and Andrew Keener) and a typically acute note from the cellist himself.