Schubert’s three mature works for violin and piano make an ideal disc-length programme, the Duo Sonata (1817) expanding on the 18th-century models that informed the three ‘sonatinas’ of the previous year, before the full power of the tragic composer’s late music is distilled in the fearsome technical challenges of the B minor Rondo (1826) and C major Fantasy (1827). Viktoria Mullova lavishes her laser-like focus and intense musicality on these works, sometimes eschewing tonal beauty and even on occasion the last degree of accuracy in favour of fervent expressivity.

Mullova remains faithful to her Guadagnini violin, gut-strung and played with a classical bow. Accompanying the change of repertoire from Beethoven (Onyx, 6/21) to Schubert, however, there have also been changes of piano, record label and recording studio. Beatson relinquishes his 1805 Walter copy for an 1819 Graf, again from the atelier of Paul McNulty – an instrument whose subtlety and range of voices is ideally suited to music of such emotional and technical range. But the move from the concert-hall ambience of Wyastone Leys to the new, more compact Ayriel Studios, overlooking the North York Moors, results in a more constricted recorded sound, in which the balance between violin and piano feels unsettled, the instruments seeming to shift in and out of parity with each other. In faster, louder music – the Scherzo of the Sonata, for example, or much of the Rondo – the Graf holds its own in the discourse, and the shimmering opening of the Fantasy is as beguiling as it ever should be. In more lyrical passages, though, the effect obscures rather than clarifies the dialogue between the voices.

Nevertheless, these three works are not commonly paired in period-instrument performances such as this, and concerns about the sound recede when considered against the blazing commitment and consummate musicianship on display from both players.