Repentance and Sotto voce are the downbeat titles of two recent compositions by Sofia Gubaidulina but there’s nothing apologetic or retiring about the music. Now in her early eighties, Gubaidulina is exploring ever more unusual instrumental combinations: viola, double bass and two guitars in Sotto voce, cello, double bass and three guitars in Repentance. In both there are dramatic confrontations involving moods that shift between heartfelt lament and forceful defiance by way of textures that relish the full spectrum of possibilities available when such disparate string instruments are brought together; Repentance is particularly imaginative in the way – without electronics – it evokes a mixture of acoustic and what sound like electro-acoustic sonorities.

Gubaidulina’s strength has always been to rhapsodise without rambling: even on the tiny scale of the two-and-a-half-minute Serenade for solo guitar from 1960 she creates an intriguing soundscape with a disconcertingly traditional final chord. The Piano Sonata (1965) is even bolder, reflecting awareness of the Western European and American avant-gardes in its use of percussive effects alongside jazz-inspired riffs to create a remarkably convincing rethinking of time-honoured sonata principles.

With Alfred Schnittke and Galina Ustvolskaya no longer on the scene, Gubaidulina shows how viable the post Shostakovich explosion of Russian compositional activity has remained. It’s a pity that this admirable disc couldn’t have included her still more recent So sei es for violin, double bass and percussion (2013). But even without that, this release is a must for its substantial additions to the still-expanding Gubaidulina discography.