It looked an enervating prospect: an entire disc devoted to Bach family members who in several cases are too obscure for any musical encyclopaedia smaller than Grove. The result – consistently well played on an organ in Melk Abbey, Austria – quickly banishes boredom to prove an improbable artistic success, aided by a beautifully austere cover design.

Heinrich Bach died in 1692, but the chorale prelude with which this CD begins sounds so pleasantly old-fashioned as to imply a 16th rather than 17th-century composer. By contrast, the Prelude and Fugue in E Flat by Heinrich’s son, the underrated Johann Christoph Bach (1642-1703), second cousin of Johann Sebastian), could easily be mistaken for Buxtehude. The Fugue in C Minor by a much better known figure, WF Bach, likewise possesses real distinction, tending to justify the hopes which JSB placed in his eldest son, and inspiring in at least one listener a desire to track down the rest of WF’s organ output.

Uniquely among the compositions on this release, the remarkably effective fugue by Johann Christian Bach – not the eponymous ‘English Bach’, but a younger man whose dates were 1745-1814 – is based on the B-A-C-H theme afterwards so profitable to Liszt, Schumann and Reger. Johann Ernst Bach (1722-77), a third cousin of JSB, contributes a more traditional but admirably solid Fantasy and Fugue in F.

Occasional let-downs occur. The five-movement partita by Johann Ernst’s father Johann Bernhard Bach (1676-1749) is a singularly unimaginative reworking of the hymn Thou, Prince of Peace, Lord Jesus Christ. A chorale prelude by Johann Michael Bach (1648-94), father-inlaw of JSB, is considerably more enterprising, but something went awry with the recorded balance in Sergio Militello’s performance: the accompaniment almost disappears, thus making the chorale melody (with its buzzing reeds) seem to float in space, unsupported.

Despite the odd glitch here and there, the basic recording quality is good.