JS Bach hovers very audibly behind of these four wonderful works, sometimes, metaphorically speaking, even stepping forwards to take the fiddle from Reger’s hands and placing it in his own. The most obvious case in point is the 10-minute Andante con moto that closes the fourth and last of the sonatas, a ‘Reger Chaconne’ in all but name. The cumulative effect is similar to that of Bach’s own Chaconne, and so are some of the techniques employed, most particularly the rolling arpeggios towards the close of the movement.

Reger dedicated the sonatas to the German violinist, composer and publisher Willy Burmester, and while the Bachian axis is fairly obvious, the sheer variety on offer is extraordinary. The first of the four sonatas sets off to a musically imposing but technically taxing Allegro energico that resembles a sizeable concerto cadenza. A confessional Adagio follows, then a mischievous Prestissimo where chords and pizzicatos alternate, and a finale that opens like the fugue from Bach’s First Solo Violin Sonata. As to Reger’s Second Sonata, don’t be fooled by the first movement’s Allegro con grazia marking: this is playful, variegated music that operates at various tempi and dynamics, a caprice in all but name, fashioned rather in the manner of Fritz Kreisler. The Andantino is a variety of siciliano, and there’s a busy Prestissimo with fast runs, expressive double-stops and striking key changes. The Third Sonata’s first movement features wide leaps and intense chordal writing, whereas in the finale the leaps are even wider.

Ulf Wallin doesn’t so much take all this in his stride as stride into the fray with total confidence, his playing agile, tonally rich, spiky where necessary and brilliant too. A very characterful and musically engaging alternative version by Renate Eggebrecht-Kupsa (Troubadisc) very occasionally sounds over-effortful, though her connection with the music’s emotional core undeniably leaves a strong impression. But Wallin’s combination of musical sensitivity and technical excellence makes him a secure front-runner. A superb CD.