The latest addition to Ton Koopman’s monumental Buxtehude recording project is the second of two collections of trio sonatas, published in Hamburg in 1696. A number of excellent groups have previously recorded them but none with the authority and wide experience of Buxtehude’s music that Koopman can claim.

His colleagues in these performances themselves bring exceptional qualities to the music. Catherine Manson is a subtle yet spirited violinist, who consistently delights and surprises. Paolo Pandolfo, one of the finest viol players of our day, ensures that the viol is always the equal of the violin, and Mike Fentross contributes exquisite improvisatory introductions and ornamented accompaniments on the lute that precisely complement those of Koopman on the keyboards. In this repertoire, their chamber music playing is surely without peer.

The key to listening to Buxtehude’s trio sonatas is an awareness of the stylus phantasicus: a finely honed style of composing and performing, specifically favoured by Buxtehude and his north German contemporaries, that conveys the impression of unrestrained improvisation.

The seven trio sonatas of Op 2 each offer a succession of six to eight movements, played without pause, that alternate between superbly modulated slow and fast tempi, and improvisatory and contrapuntal textures, dominated by a dazzling array of ostinato variations. Along the way the listener encounters solos, dialogues and conversations, sublime suspensions, jaunty syncopated and insistent concitato (agitated repeated-note) rhythms and expressive, occasionally modal harmonies that compensate for the somewhat lean melodic fare. Wonderfully warm, eventful and ultimately deeply satisfying performances.