Imitation, extrapolation, improvisation, composition: all are part of the truly fluent musician’s education and evolution. So it was for Mozart; so it is for musical “completist” – to give the term a new spin – educator, writer and broadcaster Timothy Jones; and for period-instrument violinist Rachel Podger and (forte) pianist Christopher Glynn.

Rachel Podger

Coming some years after Podger’s and Gary Cooper’s marvellous, widely acclaimed complete period-instrument recordings of Mozart violin sonatas, also for Channel Classics, these “World premiere recordings of six sonata-allegros and a fantasia for violin and piano, completed by Timothy Jones” are an utter delight from start to finish. They are also a provocative pendant of sorts to those recordings, with Jones offering two of his many different completions for each of the three sonata fragments: a Sonata in B flat for piano and violin from 1782, a Sonata in A for piano and violin from 1784, and a Sonata in G for piano and violin from 1789. In between the two sets of alternative...